{
  "id": "/harbin/festivals/1981",
  "place": {
    "id": "2037013",
    "slug": "harbin",
    "name": "Harbin",
    "region": "Heilongjiang, China",
    "country": "CN",
    "lat": 45.75,
    "lon": 126.65,
    "elevation_m": 140,
    "tz": "Asia/Shanghai"
  },
  "year": 1981,
  "tradition": "smarta",
  "method": "pac-rp@2026.1",
  "ruleset": "2026.3-draft",
  "rulings": [
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-01-02",
      "festival": "ekadashi",
      "name": "Saphalā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-02",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 5745,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-01-01T08:50:38+08:00",
          "utc": "1981-01-01T00:50:38Z",
          "ms": 347158238316.0212
        },
        "end": {
          "local": "1981-01-02T11:05:34+08:00",
          "utc": "1981-01-02T03:05:34Z",
          "ms": 347252734100.33154
        },
        "month": {
          "amanta": 8,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-01-01T08:50:38+08:00",
          "utc": "1981-01-01T00:50:38Z",
          "ms": 347158238316.0212
        },
        "end": {
          "local": "1981-01-02T11:05:34+08:00",
          "utc": "1981-01-02T03:05:34Z",
          "ms": 347252734100.33154
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-01-01",
          "window": {
            "start": {
              "local": "1981-01-01T07:14:53+08:00",
              "utc": "1980-12-31T23:14:53Z",
              "ms": 347152493497.29254
            },
            "end": {
              "local": "1981-01-01T07:14:53+08:00",
              "utc": "1980-12-31T23:14:53Z",
              "ms": 347152493497.29254
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-01-02",
          "window": {
            "start": {
              "local": "1981-01-02T07:14:55+08:00",
              "utc": "1981-01-01T23:14:55Z",
              "ms": 347238895256.95135
            },
            "end": {
              "local": "1981-01-02T07:14:55+08:00",
              "utc": "1981-01-01T23:14:55Z",
              "ms": 347238895256.95135
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 08:51 on Thu 1 Jan to 11:06 on Fri 2 Jan.",
          "fact": "1981-01-01T00:50:38Z → 1981-01-02T03:05:34Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 07:15 on the 1st and 07:15 on the 2nd.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 1st and is on the 2nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 5745 s"
        },
        {
          "step": "ruling",
          "text": "Saphalā Ekādaśī, Harbin, 1981: Friday 2 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saphalā Ekādaśī 1981 falls on Friday 2 January. Ekādaśī runs from 08:51 on Thu 1 Jan to 11:06 on Fri 2 Jan and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-01-02",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-01-03",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-03",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 6322,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-01-03T12:55:55+08:00",
          "utc": "1981-01-03T04:55:55Z",
          "ms": 347345755300.01794
        },
        "end": {
          "local": "1981-01-04T14:16:32+08:00",
          "utc": "1981-01-04T06:16:32Z",
          "ms": 347436992198.3991
        },
        "month": {
          "amanta": 8,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-01-03T12:55:55+08:00",
          "utc": "1981-01-03T04:55:55Z",
          "ms": 347345755300.01794
        },
        "end": {
          "local": "1981-01-04T14:16:32+08:00",
          "utc": "1981-01-04T06:16:32Z",
          "ms": 347436992198.3991
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-01-03",
          "window": {
            "start": {
              "local": "1981-01-03T16:00:54+08:00",
              "utc": "1981-01-03T08:00:54Z",
              "ms": 347356854172.8398
            },
            "end": {
              "local": "1981-01-03T18:02:46+08:00",
              "utc": "1981-01-03T10:02:46Z",
              "ms": 347364165715.3822
            }
          },
          "covered_min": 122,
          "window_min": 122,
          "qualifies": true
        },
        {
          "local_date": "1981-01-04",
          "window": {
            "start": {
              "local": "1981-01-04T16:01:54+08:00",
              "utc": "1981-01-04T08:01:54Z",
              "ms": 347443313798.2255
            },
            "end": {
              "local": "1981-01-04T18:03:37+08:00",
              "utc": "1981-01-04T10:03:37Z",
              "ms": 347450616553.7815
            }
          },
          "covered_min": 0,
          "window_min": 122,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 12:56 on Sat 3 Jan to 14:17 on Sun 4 Jan.",
          "fact": "1981-01-03T04:55:55Z → 1981-01-04T06:16:32Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:01–18:03 on the 3rd, 16:02–18:04 on the 4th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 122 of 122 minutes on the 3rd and 0 of 122 on the 4th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 6322 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Saturday 3 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-03",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-03",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Saturday 3 January. Trayodaśī runs from 12:56 on Sat 3 Jan to 14:17 on Sun 4 Jan and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-01-03",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-01-04",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-04",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 29347,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-01-04T14:16:32+08:00",
          "utc": "1981-01-04T06:16:32Z",
          "ms": 347436992198.3991
        },
        "end": {
          "local": "1981-01-05T15:05:38+08:00",
          "utc": "1981-01-05T07:05:38Z",
          "ms": 347526338183.52924
        },
        "month": {
          "amanta": 8,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-01-04T14:16:32+08:00",
          "utc": "1981-01-04T06:16:32Z",
          "ms": 347436992198.3991
        },
        "end": {
          "local": "1981-01-05T15:05:38+08:00",
          "utc": "1981-01-05T07:05:38Z",
          "ms": 347526338183.52924
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-01-04",
          "window": {
            "start": {
              "local": "1981-01-04T23:14:19+08:00",
              "utc": "1981-01-04T15:14:19Z",
              "ms": 347469259131.5603
            },
            "end": {
              "local": "1981-01-05T00:02:19+08:00",
              "utc": "1981-01-04T16:02:19Z",
              "ms": 347472139131.5603
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-01-05",
          "window": {
            "start": {
              "local": "1981-01-05T23:14:45+08:00",
              "utc": "1981-01-05T15:14:45Z",
              "ms": 347555685406.8075
            },
            "end": {
              "local": "1981-01-06T00:02:45+08:00",
              "utc": "1981-01-05T16:02:45Z",
              "ms": 347558565406.8075
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 14:17 on Sun 4 Jan to 15:06 on Mon 5 Jan.",
          "fact": "1981-01-04T06:16:32Z → 1981-01-05T07:05:38Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:14–00:02 on the 4th, 23:15–00:03 on the 5th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 48 of 48 minutes on the 4th and 0 of 48 on the 5th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 29347 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Sunday 4 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-04",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-04",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Sunday 4 January. Caturdaśī runs from 14:17 on Sun 4 Jan to 15:06 on Mon 5 Jan and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-01-04",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-01-10",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-10",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1277,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-01-09T13:42:01+08:00",
          "utc": "1981-01-09T05:42:01Z",
          "ms": 347866921073.54486
        },
        "end": {
          "local": "1981-01-10T12:26:18+08:00",
          "utc": "1981-01-10T04:26:18Z",
          "ms": 347948778286.5653
        },
        "month": {
          "amanta": 9,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-01-09T13:42:01+08:00",
          "utc": "1981-01-09T05:42:01Z",
          "ms": 347866921073.54486
        },
        "end": {
          "local": "1981-01-10T12:26:18+08:00",
          "utc": "1981-01-10T04:26:18Z",
          "ms": 347948778286.5653
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-01-09",
          "window": {
            "start": {
              "local": "1981-01-09T11:16:36+08:00",
              "utc": "1981-01-09T03:16:36Z",
              "ms": 347858195690.94806
            },
            "end": {
              "local": "1981-01-09T12:04:36+08:00",
              "utc": "1981-01-09T04:04:36Z",
              "ms": 347861075690.94806
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-01-10",
          "window": {
            "start": {
              "local": "1981-01-10T11:17:01+08:00",
              "utc": "1981-01-10T03:17:01Z",
              "ms": 347944620823.749
            },
            "end": {
              "local": "1981-01-10T12:05:01+08:00",
              "utc": "1981-01-10T04:05:01Z",
              "ms": 347947500823.749
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 13:42 on Fri 9 Jan to 12:26 on Sat 10 Jan.",
          "fact": "1981-01-09T05:42:01Z → 1981-01-10T04:26:18Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:17–12:05 on the 9th, 11:17–12:05 on the 10th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 0 of 48 minutes on the 9th and 48 of 48 on the 10th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 1277 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Saturday 10 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-10",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-10",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Saturday 10 January. Caturthī runs from 13:42 on Fri 9 Jan to 12:26 on Sat 10 Jan and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-01-10",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/bhogi",
      "festival": "bhogi",
      "name": "Bhogi",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-13",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 42389,
      "anga": {
        "type": "sankranti",
        "index": 9,
        "key": "makara",
        "name": "Makara",
        "start": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        },
        "end": {
          "local": "1981-02-12T17:28:15+08:00",
          "utc": "1981-02-12T09:28:15Z",
          "ms": 350818095129.987
        }
      },
      "span": {
        "of": "transit",
        "start": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        },
        "end": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        }
      },
      "kaala": "sunset-day",
      "days": [
        {
          "local_date": "1981-01-14",
          "window": {
            "start": {
              "local": "1981-01-13T16:12:07+08:00",
              "utc": "1981-01-13T08:12:07Z",
              "ms": 348221526707.2466
            },
            "end": {
              "local": "1981-01-14T16:13:22+08:00",
              "utc": "1981-01-14T08:13:22Z",
              "ms": 348308002006.90717
            }
          },
          "covered_min": 1,
          "window_min": 1441,
          "qualifies": true
        },
        {
          "local_date": "1981-01-15",
          "window": {
            "start": {
              "local": "1981-01-14T16:13:22+08:00",
              "utc": "1981-01-14T08:13:22Z",
              "ms": 348308002006.90717
            },
            "end": {
              "local": "1981-01-15T16:14:38+08:00",
              "utc": "1981-01-15T08:14:38Z",
              "ms": 348394478496.13605
            }
          },
          "covered_min": 0,
          "window_min": 1441,
          "qualifies": false
        }
      ],
      "follows": {
        "festival": "pongal",
        "name": "Pongal",
        "local_date": "1981-01-14",
        "days": -1
      },
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "The Sun enters Makara at 04:27 on Wed 14 Jan.",
          "fact": "1981-01-13T20:26:53Z · nirayana, lahiri-iae1985"
        },
        {
          "step": "kaala",
          "text": "The day is counted from the sunset before it to its own sunset: the day of the 14th ends at 16:13, and the day of the 15th ends at 16:15.",
          "fact": "sunset-day: sunset-to-sunset · sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "The festival is kept on the day of the transit, the day counted from the sunset before it: a transit after sunset belongs to the next day. The transit falls between the sunsets of the 13th and the 14th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 106"
        },
        {
          "step": "tie_break",
          "text": "An instant falls in one day and no other. No tie-break is needed.",
          "fact": "day counted from sunset → only-day · margin 42389 s"
        },
        {
          "step": "counted",
          "text": "Bhogi is kept the day before Pongal: Wednesday 14 January is the day taken above.",
          "fact": "follows: pongal − 1 d"
        },
        {
          "step": "ruling",
          "text": "Bhogi, Harbin, 1981: Tuesday 13 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "solar",
        "id": "bhogi",
        "follows": {
          "festival": "pongal",
          "days": -1
        },
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Makaradi — Makaradi snana, Magh Bihu (Assam), Tila samkranti, Pongal (S. India), Bhogi (S. India — on the day before Pongal), Mattu Pongal (S. India — on the day after Pongal)."
          },
          {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Tamil rule: In the Tamil districts the rule is that when a samkranti takes place before sunset, the month begins on the same day, while if it takes place after sunset the month begins on the following day."
          }
        ],
        "rashi": "Makara",
        "day_from": "sunset"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-13",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-13",
          "confidence": "determinate"
        },
        {
          "kind": "reckoning",
          "id": "civil-day",
          "local_date": "1981-01-13",
          "statement": "Counted from midnight",
          "reference": {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The following festivals are observed according to the day of Sun's transit into rasis (Ravi-samkramana). For this purpose the day has been taken to begin from midnight, i.e., when the samkramana takes place after midnight, the festival relating to the samkramana is to be observed on the following day."
          }
        },
        {
          "kind": "reckoning",
          "id": "sunrise-day",
          "local_date": "1981-01-12",
          "statement": "Counted from sunrise (the Orissa rule)",
          "reference": {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Orissa rule: In Orissa the solar months of the Amli and Vilayati eras begin civilly on the same day (sunrise to next sunrise) as the samkranti, irrespective of whether this takes place before or after midnight."
          }
        }
      ],
      "quote": "In Harbin, Bhogi 1981 falls on Tuesday 13 January. It is kept the day before Pongal, which falls on Wednesday 14 January. The Sun enters Makara at 04:27 on Wed 14 Jan. The rule counts the day from sunset to sunset, and the transit falls between the sunsets of the 13th and the 14th. Counted from sunrise, as in Orissa, it is 12 January.",
      "cite": "https://ahargana.org/harbin/festivals/1981/bhogi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pongal",
      "festival": "pongal",
      "name": "Pongal",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-14",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 42389,
      "anga": {
        "type": "sankranti",
        "index": 9,
        "key": "makara",
        "name": "Makara",
        "start": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        },
        "end": {
          "local": "1981-02-12T17:28:15+08:00",
          "utc": "1981-02-12T09:28:15Z",
          "ms": 350818095129.987
        }
      },
      "span": {
        "of": "transit",
        "start": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        },
        "end": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        }
      },
      "kaala": "sunset-day",
      "days": [
        {
          "local_date": "1981-01-14",
          "window": {
            "start": {
              "local": "1981-01-13T16:12:07+08:00",
              "utc": "1981-01-13T08:12:07Z",
              "ms": 348221526707.2466
            },
            "end": {
              "local": "1981-01-14T16:13:22+08:00",
              "utc": "1981-01-14T08:13:22Z",
              "ms": 348308002006.90717
            }
          },
          "covered_min": 1,
          "window_min": 1441,
          "qualifies": true
        },
        {
          "local_date": "1981-01-15",
          "window": {
            "start": {
              "local": "1981-01-14T16:13:22+08:00",
              "utc": "1981-01-14T08:13:22Z",
              "ms": 348308002006.90717
            },
            "end": {
              "local": "1981-01-15T16:14:38+08:00",
              "utc": "1981-01-15T08:14:38Z",
              "ms": 348394478496.13605
            }
          },
          "covered_min": 0,
          "window_min": 1441,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "The Sun enters Makara at 04:27 on Wed 14 Jan.",
          "fact": "1981-01-13T20:26:53Z · nirayana, lahiri-iae1985"
        },
        {
          "step": "kaala",
          "text": "The day is counted from the sunset before it to its own sunset: the day of the 14th ends at 16:13, and the day of the 15th ends at 16:15.",
          "fact": "sunset-day: sunset-to-sunset · sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "The festival is kept on the day of the transit, the day counted from the sunset before it: a transit after sunset belongs to the next day. The transit falls between the sunsets of the 13th and the 14th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 106"
        },
        {
          "step": "tie_break",
          "text": "An instant falls in one day and no other. No tie-break is needed.",
          "fact": "day counted from sunset → only-day · margin 42389 s"
        },
        {
          "step": "ruling",
          "text": "Pongal, Harbin, 1981: Wednesday 14 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "solar",
        "id": "pongal",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Makaradi — Makaradi snana, Magh Bihu (Assam), Tila samkranti, Pongal (S. India), Bhogi (S. India — on the day before Pongal), Mattu Pongal (S. India — on the day after Pongal)."
          },
          {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Tamil rule: In the Tamil districts the rule is that when a samkranti takes place before sunset, the month begins on the same day, while if it takes place after sunset the month begins on the following day."
          }
        ],
        "not_evaluated": "The rule that heads the solar festivals, the day \"taken to begin from midnight\" (p. 106), is not applied to Pongal. It is kept on the first day of the month of Makara as the Tamil districts count it, a transit after sunset going to the next day (p. 244); the Rashtriya Panchang prints Pongal so.",
        "rashi": "Makara",
        "day_from": "sunset"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-14",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-14",
          "confidence": "determinate"
        },
        {
          "kind": "reckoning",
          "id": "civil-day",
          "local_date": "1981-01-14",
          "statement": "Counted from midnight",
          "reference": {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The following festivals are observed according to the day of Sun's transit into rasis (Ravi-samkramana). For this purpose the day has been taken to begin from midnight, i.e., when the samkramana takes place after midnight, the festival relating to the samkramana is to be observed on the following day."
          }
        },
        {
          "kind": "reckoning",
          "id": "sunrise-day",
          "local_date": "1981-01-13",
          "statement": "Counted from sunrise (the Orissa rule)",
          "reference": {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Orissa rule: In Orissa the solar months of the Amli and Vilayati eras begin civilly on the same day (sunrise to next sunrise) as the samkranti, irrespective of whether this takes place before or after midnight."
          }
        }
      ],
      "quote": "In Harbin, Pongal 1981 falls on Wednesday 14 January. The Sun enters Makara at 04:27 on Wed 14 Jan. The rule counts the day from sunset to sunset, and the transit falls between the sunsets of the 13th and the 14th. Counted from sunrise, as in Orissa, it is 13 January.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pongal",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/makara-sankranti",
      "festival": "makara-sankranti",
      "name": "Makara Saṅkrānti",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-14",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 16013,
      "anga": {
        "type": "sankranti",
        "index": 9,
        "key": "makara",
        "name": "Makara",
        "start": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        },
        "end": {
          "local": "1981-02-12T17:28:15+08:00",
          "utc": "1981-02-12T09:28:15Z",
          "ms": 350818095129.987
        }
      },
      "span": {
        "of": "transit",
        "start": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        },
        "end": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        }
      },
      "kaala": "civil-day",
      "days": [
        {
          "local_date": "1981-01-13",
          "window": {
            "start": {
              "local": "1981-01-13T00:00:00+08:00",
              "utc": "1981-01-12T16:00:00Z",
              "ms": 348163200000
            },
            "end": {
              "local": "1981-01-14T00:00:00+08:00",
              "utc": "1981-01-13T16:00:00Z",
              "ms": 348249600000
            }
          },
          "covered_min": 0,
          "window_min": 1440,
          "qualifies": false
        },
        {
          "local_date": "1981-01-14",
          "window": {
            "start": {
              "local": "1981-01-14T00:00:00+08:00",
              "utc": "1981-01-13T16:00:00Z",
              "ms": 348249600000
            },
            "end": {
              "local": "1981-01-15T00:00:00+08:00",
              "utc": "1981-01-14T16:00:00Z",
              "ms": 348336000000
            }
          },
          "covered_min": 1,
          "window_min": 1440,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "The Sun enters Makara at 04:27 on Wed 14 Jan.",
          "fact": "1981-01-13T20:26:53Z · nirayana, lahiri-iae1985"
        },
        {
          "step": "kaala",
          "text": "The day is counted from midnight to midnight, on the clock of Harbin.",
          "fact": "civil-day: midnight-to-midnight · Asia/Shanghai"
        },
        {
          "step": "rule",
          "text": "The festival is kept on the day of the transit, the day counted from midnight. The transit falls on the 14th, not the 13th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 106"
        },
        {
          "step": "tie_break",
          "text": "An instant falls in one day and no other. No tie-break is needed.",
          "fact": "day counted from midnight → only-day · margin 16013 s"
        },
        {
          "step": "ruling",
          "text": "Makara Saṅkrānti, Harbin, 1981: Wednesday 14 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "solar",
        "id": "makara-sankranti",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Makaradi — Makaradi snana, Magh Bihu (Assam), Tila samkranti, Pongal (S. India), Bhogi (S. India — on the day before Pongal), Mattu Pongal (S. India — on the day after Pongal)."
          },
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The following festivals are observed according to the day of Sun's transit into rasis (Ravi-samkramana). For this purpose the day has been taken to begin from midnight, i.e., when the samkramana takes place after midnight, the festival relating to the samkramana is to be observed on the following day."
          }
        ],
        "rashi": "Makara",
        "day_from": "midnight"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-14",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-14",
          "confidence": "determinate"
        },
        {
          "kind": "reckoning",
          "id": "sunrise-day",
          "local_date": "1981-01-13",
          "statement": "Counted from sunrise (the Orissa rule)",
          "reference": {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Orissa rule: In Orissa the solar months of the Amli and Vilayati eras begin civilly on the same day (sunrise to next sunrise) as the samkranti, irrespective of whether this takes place before or after midnight."
          }
        },
        {
          "kind": "reckoning",
          "id": "sunset-rule",
          "local_date": "1981-01-14",
          "statement": "Past sunset, the next day (the Tamil rule)",
          "reference": {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Tamil rule: In the Tamil districts the rule is that when a samkranti takes place before sunset, the month begins on the same day, while if it takes place after sunset the month begins on the following day."
          }
        }
      ],
      "quote": "In Harbin, Makara Saṅkrānti 1981 falls on Wednesday 14 January. The Sun enters Makara at 04:27 on Wed 14 Jan, and the rule counts the day from midnight. Counted from sunrise, as in Orissa, it is 13 January.",
      "cite": "https://ahargana.org/harbin/festivals/1981/makara-sankranti",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/mattu-pongal",
      "festival": "mattu-pongal",
      "name": "Mattu Pongal",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-15",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 42389,
      "anga": {
        "type": "sankranti",
        "index": 9,
        "key": "makara",
        "name": "Makara",
        "start": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        },
        "end": {
          "local": "1981-02-12T17:28:15+08:00",
          "utc": "1981-02-12T09:28:15Z",
          "ms": 350818095129.987
        }
      },
      "span": {
        "of": "transit",
        "start": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        },
        "end": {
          "local": "1981-01-14T04:26:53+08:00",
          "utc": "1981-01-13T20:26:53Z",
          "ms": 348265613318.17065
        }
      },
      "kaala": "sunset-day",
      "days": [
        {
          "local_date": "1981-01-14",
          "window": {
            "start": {
              "local": "1981-01-13T16:12:07+08:00",
              "utc": "1981-01-13T08:12:07Z",
              "ms": 348221526707.2466
            },
            "end": {
              "local": "1981-01-14T16:13:22+08:00",
              "utc": "1981-01-14T08:13:22Z",
              "ms": 348308002006.90717
            }
          },
          "covered_min": 1,
          "window_min": 1441,
          "qualifies": true
        },
        {
          "local_date": "1981-01-15",
          "window": {
            "start": {
              "local": "1981-01-14T16:13:22+08:00",
              "utc": "1981-01-14T08:13:22Z",
              "ms": 348308002006.90717
            },
            "end": {
              "local": "1981-01-15T16:14:38+08:00",
              "utc": "1981-01-15T08:14:38Z",
              "ms": 348394478496.13605
            }
          },
          "covered_min": 0,
          "window_min": 1441,
          "qualifies": false
        }
      ],
      "follows": {
        "festival": "pongal",
        "name": "Pongal",
        "local_date": "1981-01-14",
        "days": 1
      },
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "The Sun enters Makara at 04:27 on Wed 14 Jan.",
          "fact": "1981-01-13T20:26:53Z · nirayana, lahiri-iae1985"
        },
        {
          "step": "kaala",
          "text": "The day is counted from the sunset before it to its own sunset: the day of the 14th ends at 16:13, and the day of the 15th ends at 16:15.",
          "fact": "sunset-day: sunset-to-sunset · sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "The festival is kept on the day of the transit, the day counted from the sunset before it: a transit after sunset belongs to the next day. The transit falls between the sunsets of the 13th and the 14th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 106"
        },
        {
          "step": "tie_break",
          "text": "An instant falls in one day and no other. No tie-break is needed.",
          "fact": "day counted from sunset → only-day · margin 42389 s"
        },
        {
          "step": "counted",
          "text": "Mattu Pongal is kept the day after Pongal: Wednesday 14 January is the day taken above.",
          "fact": "follows: pongal + 1 d"
        },
        {
          "step": "ruling",
          "text": "Mattu Pongal, Harbin, 1981: Thursday 15 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "solar",
        "id": "mattu-pongal",
        "follows": {
          "festival": "pongal",
          "days": 1
        },
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Makaradi — Makaradi snana, Magh Bihu (Assam), Tila samkranti, Pongal (S. India), Bhogi (S. India — on the day before Pongal), Mattu Pongal (S. India — on the day after Pongal)."
          },
          {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Tamil rule: In the Tamil districts the rule is that when a samkranti takes place before sunset, the month begins on the same day, while if it takes place after sunset the month begins on the following day."
          }
        ],
        "rashi": "Makara",
        "day_from": "sunset"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-15",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-15",
          "confidence": "determinate"
        },
        {
          "kind": "reckoning",
          "id": "civil-day",
          "local_date": "1981-01-15",
          "statement": "Counted from midnight",
          "reference": {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The following festivals are observed according to the day of Sun's transit into rasis (Ravi-samkramana). For this purpose the day has been taken to begin from midnight, i.e., when the samkramana takes place after midnight, the festival relating to the samkramana is to be observed on the following day."
          }
        },
        {
          "kind": "reckoning",
          "id": "sunrise-day",
          "local_date": "1981-01-14",
          "statement": "Counted from sunrise (the Orissa rule)",
          "reference": {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Orissa rule: In Orissa the solar months of the Amli and Vilayati eras begin civilly on the same day (sunrise to next sunrise) as the samkranti, irrespective of whether this takes place before or after midnight."
          }
        }
      ],
      "quote": "In Harbin, Mattu Pongal 1981 falls on Thursday 15 January. It is kept the day after Pongal, which falls on Wednesday 14 January. The Sun enters Makara at 04:27 on Wed 14 Jan. The rule counts the day from sunset to sunset, and the transit falls between the sunsets of the 13th and the 14th. Counted from sunrise, as in Orissa, it is 14 January.",
      "cite": "https://ahargana.org/harbin/festivals/1981/mattu-pongal",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-01-16",
      "festival": "ekadashi",
      "name": "Putradā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 23502,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-01-16T00:38:59+08:00",
          "utc": "1981-01-15T16:38:59Z",
          "ms": 348424738877.58954
        },
        "end": {
          "local": "1981-01-16T22:25:46+08:00",
          "utc": "1981-01-16T14:25:46Z",
          "ms": 348503145853.60675
        },
        "month": {
          "amanta": 9,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-01-16T00:38:59+08:00",
          "utc": "1981-01-15T16:38:59Z",
          "ms": 348424738877.58954
        },
        "end": {
          "local": "1981-01-16T22:25:46+08:00",
          "utc": "1981-01-16T14:25:46Z",
          "ms": 348503145853.60675
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-01-16",
          "window": {
            "start": {
              "local": "1981-01-16T07:10:41+08:00",
              "utc": "1981-01-15T23:10:41Z",
              "ms": 348448240813.3922
            },
            "end": {
              "local": "1981-01-16T07:10:41+08:00",
              "utc": "1981-01-15T23:10:41Z",
              "ms": 348448240813.3922
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-01-17",
          "window": {
            "start": {
              "local": "1981-01-17T07:10:03+08:00",
              "utc": "1981-01-16T23:10:03Z",
              "ms": 348534603242.1832
            },
            "end": {
              "local": "1981-01-17T07:10:03+08:00",
              "utc": "1981-01-16T23:10:03Z",
              "ms": 348534603242.1832
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 00:39 on Fri 16 Jan to 22:26 on Fri 16 Jan.",
          "fact": "1981-01-15T16:38:59Z → 1981-01-16T14:25:46Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 07:11 on the 16th and 07:10 on the 17th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 16th and is not on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 23502 s"
        },
        {
          "step": "ruling",
          "text": "Putradā Ekādaśī, Harbin, 1981: Friday 16 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Putradā Ekādaśī 1981 falls on Friday 16 January. Ekādaśī runs from 00:39 on Fri 16 Jan to 22:26 on Fri 16 Jan and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-01-16",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-01-18",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-18",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 475,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-01-17T20:19:15+08:00",
          "utc": "1981-01-17T12:19:15Z",
          "ms": 348581955203.7646
        },
        "end": {
          "local": "1981-01-18T18:25:11+08:00",
          "utc": "1981-01-18T10:25:11Z",
          "ms": 348661510618.66455
        },
        "month": {
          "amanta": 9,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-01-17T20:19:15+08:00",
          "utc": "1981-01-17T12:19:15Z",
          "ms": 348581955203.7646
        },
        "end": {
          "local": "1981-01-18T18:25:11+08:00",
          "utc": "1981-01-18T10:25:11Z",
          "ms": 348661510618.66455
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-01-17",
          "window": {
            "start": {
              "local": "1981-01-17T16:17:15+08:00",
              "utc": "1981-01-17T08:17:15Z",
              "ms": 348567434785.7178
            },
            "end": {
              "local": "1981-01-17T18:16:12+08:00",
              "utc": "1981-01-17T10:16:12Z",
              "ms": 348574571910.6261
            }
          },
          "covered_min": 0,
          "window_min": 119,
          "qualifies": false
        },
        {
          "local_date": "1981-01-18",
          "window": {
            "start": {
              "local": "1981-01-18T16:18:34+08:00",
              "utc": "1981-01-18T08:18:34Z",
              "ms": 348653914461.59515
            },
            "end": {
              "local": "1981-01-18T18:17:15+08:00",
              "utc": "1981-01-18T10:17:15Z",
              "ms": 348661035305.58875
            }
          },
          "covered_min": 119,
          "window_min": 119,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 20:19 on Sat 17 Jan to 18:25 on Sun 18 Jan.",
          "fact": "1981-01-17T12:19:15Z → 1981-01-18T10:25:11Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:17–18:16 on the 17th, 16:19–18:17 on the 18th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 119 minutes on the 17th and 119 of 119 on the 18th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 475 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Sunday 18 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-18",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-18",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Sunday 18 January. Trayodaśī runs from 20:19 on Sat 17 Jan to 18:25 on Sun 18 Jan and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-01-18",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-01-23",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-01-23",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 14728,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-01-23T15:26:36+08:00",
          "utc": "1981-01-23T07:26:36Z",
          "ms": 349082796315.67535
        },
        "end": {
          "local": "1981-01-24T16:37:24+08:00",
          "utc": "1981-01-24T08:37:24Z",
          "ms": 349173443840.836
        },
        "month": {
          "amanta": 9,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-01-23T15:26:36+08:00",
          "utc": "1981-01-23T07:26:36Z",
          "ms": 349082796315.67535
        },
        "end": {
          "local": "1981-01-24T16:37:24+08:00",
          "utc": "1981-01-24T08:37:24Z",
          "ms": 349173443840.836
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-01-23",
          "window": {
            "start": {
              "local": "1981-01-23T19:39:50+08:00",
              "utc": "1981-01-23T11:39:50Z",
              "ms": 349097990331.5022
            },
            "end": {
              "local": "1981-01-23T19:39:50+08:00",
              "utc": "1981-01-23T11:39:50Z",
              "ms": 349097990331.5022
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-01-24",
          "window": {
            "start": {
              "local": "1981-01-24T20:42:52+08:00",
              "utc": "1981-01-24T12:42:52Z",
              "ms": 349188171723.96606
            },
            "end": {
              "local": "1981-01-24T20:42:52+08:00",
              "utc": "1981-01-24T12:42:52Z",
              "ms": 349188171723.96606
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 15:27 on Fri 23 Jan to 16:37 on Sat 24 Jan.",
          "fact": "1981-01-23T07:26:36Z → 1981-01-24T08:37:24Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 19:40 on the 23rd and 20:43 on the 24th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is on the 23rd and is not on the 24th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 14728 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Friday 23 January.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-01-23",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-01-23",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Friday 23 January. Caturthī runs from 15:27 on Fri 23 Jan to 16:37 on Sat 24 Jan and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-01-23",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-02-01",
      "festival": "ekadashi",
      "name": "Ṣaṭtilā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-01",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 889,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-01-31T05:48:34+08:00",
          "utc": "1981-01-30T21:48:34Z",
          "ms": 349739313714.7193
        },
        "end": {
          "local": "1981-02-01T07:10:57+08:00",
          "utc": "1981-01-31T23:10:57Z",
          "ms": 349830657094.1563
        },
        "month": {
          "amanta": 9,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-01-31T05:48:34+08:00",
          "utc": "1981-01-30T21:48:34Z",
          "ms": 349739313714.7193
        },
        "end": {
          "local": "1981-02-01T07:10:57+08:00",
          "utc": "1981-01-31T23:10:57Z",
          "ms": 349830657094.1563
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-01-31",
          "window": {
            "start": {
              "local": "1981-01-31T06:57:18+08:00",
              "utc": "1981-01-30T22:57:18Z",
              "ms": 349743437989.8039
            },
            "end": {
              "local": "1981-01-31T06:57:18+08:00",
              "utc": "1981-01-30T22:57:18Z",
              "ms": 349743437989.8039
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-02-01",
          "window": {
            "start": {
              "local": "1981-02-01T06:56:08+08:00",
              "utc": "1981-01-31T22:56:08Z",
              "ms": 349829767858.1229
            },
            "end": {
              "local": "1981-02-01T06:56:08+08:00",
              "utc": "1981-01-31T22:56:08Z",
              "ms": 349829767858.1229
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "paraviddha",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 05:49 on Sat 31 Jan to 07:11 on Sun 1 Feb.",
          "fact": "1981-01-30T21:48:34Z → 1981-01-31T23:10:57Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 06:57 on the 31st and 06:56 on the 1st.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 31st and is on the 1st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Both sunrises qualify. Paraviddhā: the second is taken.",
          "fact": "priority: paraviddha → paraviddha · margin 889 s"
        },
        {
          "step": "ruling",
          "text": "Ṣaṭtilā Ekādaśī, Harbin, 1981: Sunday 1 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-01",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-01",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Ṣaṭtilā Ekādaśī 1981 falls on Sunday 1 February. Ekādaśī runs from 05:49 on Sat 31 Jan to 07:11 on Sun 1 Feb and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-02-01",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-02-02",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-02",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 31390,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-02-02T07:54:41+08:00",
          "utc": "1981-02-01T23:54:41Z",
          "ms": 349919680829.01044
        },
        "end": {
          "local": "1981-02-03T07:58:10+08:00",
          "utc": "1981-02-02T23:58:10Z",
          "ms": 350006290221.0994
        },
        "month": {
          "amanta": 9,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-02T07:54:41+08:00",
          "utc": "1981-02-01T23:54:41Z",
          "ms": 349919680829.01044
        },
        "end": {
          "local": "1981-02-03T07:58:10+08:00",
          "utc": "1981-02-02T23:58:10Z",
          "ms": 350006290221.0994
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-02-02",
          "window": {
            "start": {
              "local": "1981-02-02T16:39:52+08:00",
              "utc": "1981-02-02T08:39:52Z",
              "ms": 349951192160.6074
            },
            "end": {
              "local": "1981-02-02T18:33:43+08:00",
              "utc": "1981-02-02T10:33:43Z",
              "ms": 349958022819.767
            }
          },
          "covered_min": 114,
          "window_min": 114,
          "qualifies": true
        },
        {
          "local_date": "1981-02-03",
          "window": {
            "start": {
              "local": "1981-02-03T16:41:21+08:00",
              "utc": "1981-02-03T08:41:21Z",
              "ms": 350037680541.68774
            },
            "end": {
              "local": "1981-02-03T18:34:49+08:00",
              "utc": "1981-02-03T10:34:49Z",
              "ms": 350044489344.48083
            }
          },
          "covered_min": 0,
          "window_min": 113,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 07:55 on Mon 2 Feb to 07:58 on Tue 3 Feb.",
          "fact": "1981-02-01T23:54:41Z → 1981-02-02T23:58:10Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:40–18:34 on the 2nd, 16:41–18:35 on the 3rd.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 114 of 114 minutes on the 2nd and 0 of 113 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 31390 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Monday 2 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Monday 2 February. Trayodaśī runs from 07:55 on Mon 2 Feb to 07:58 on Tue 3 Feb and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-02-02",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-02-03",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-03",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 25935,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-02-03T07:58:10+08:00",
          "utc": "1981-02-02T23:58:10Z",
          "ms": 350006290221.0994
        },
        "end": {
          "local": "1981-02-04T07:23:09+08:00",
          "utc": "1981-02-03T23:23:09Z",
          "ms": 350090588500.2604
        },
        "month": {
          "amanta": 9,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-03T07:58:10+08:00",
          "utc": "1981-02-02T23:58:10Z",
          "ms": 350006290221.0994
        },
        "end": {
          "local": "1981-02-04T07:23:09+08:00",
          "utc": "1981-02-03T23:23:09Z",
          "ms": 350090588500.2604
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-02-02",
          "window": {
            "start": {
              "local": "1981-02-02T23:22:47+08:00",
              "utc": "1981-02-02T15:22:47Z",
              "ms": 349975367132.45605
            },
            "end": {
              "local": "1981-02-03T00:10:47+08:00",
              "utc": "1981-02-02T16:10:47Z",
              "ms": 349978247132.45605
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-02-03",
          "window": {
            "start": {
              "local": "1981-02-03T23:22:54+08:00",
              "utc": "1981-02-03T15:22:54Z",
              "ms": 350061773552.1619
            },
            "end": {
              "local": "1981-02-04T00:10:54+08:00",
              "utc": "1981-02-03T16:10:54Z",
              "ms": 350064653552.1619
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 07:58 on Tue 3 Feb to 07:23 on Wed 4 Feb.",
          "fact": "1981-02-02T23:58:10Z → 1981-02-03T23:23:09Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:23–00:11 on the 2nd, 23:23–00:11 on the 3rd.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 0 of 48 minutes on the 2nd and 48 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 25935 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Tuesday 3 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-03",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-03",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Tuesday 3 February. Caturdaśī runs from 07:58 on Tue 3 Feb to 07:23 on Wed 4 Feb and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-02-03",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/yama-tarpana",
      "festival": "yama-tarpana",
      "name": "Yama Tarpaṇa",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-04",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1842,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-02-03T07:58:10+08:00",
          "utc": "1981-02-02T23:58:10Z",
          "ms": 350006290221.0994
        },
        "end": {
          "local": "1981-02-04T07:23:09+08:00",
          "utc": "1981-02-03T23:23:09Z",
          "ms": 350090588500.2604
        },
        "month": {
          "amanta": 9,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-03T07:58:10+08:00",
          "utc": "1981-02-02T23:58:10Z",
          "ms": 350006290221.0994
        },
        "end": {
          "local": "1981-02-04T07:23:09+08:00",
          "utc": "1981-02-03T23:23:09Z",
          "ms": 350090588500.2604
        }
      },
      "kaala": "arunodaya",
      "days": [
        {
          "local_date": "1981-02-03",
          "window": {
            "start": {
              "local": "1981-02-03T04:59:51+08:00",
              "utc": "1981-02-02T20:59:51Z",
              "ms": 349995591445.1451
            },
            "end": {
              "local": "1981-02-03T06:53:42+08:00",
              "utc": "1981-02-02T22:53:42Z",
              "ms": 350002422104.3047
            }
          },
          "covered_min": 0,
          "window_min": 114,
          "qualifies": false
        },
        {
          "local_date": "1981-02-04",
          "window": {
            "start": {
              "local": "1981-02-04T04:58:58+08:00",
              "utc": "1981-02-03T20:58:58Z",
              "ms": 350081937759.843
            },
            "end": {
              "local": "1981-02-04T06:52:27+08:00",
              "utc": "1981-02-03T22:52:27Z",
              "ms": 350088746562.6361
            }
          },
          "covered_min": 113,
          "window_min": 113,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 07:58 on Tue 3 Feb to 07:23 on Wed 4 Feb.",
          "fact": "1981-02-02T23:58:10Z → 1981-02-03T23:23:09Z"
        },
        {
          "step": "kaala",
          "text": "Aruṇodaya is 2 muhūrtas before sunrise: 05:00–06:54 on the 3rd, 04:59–06:52 on the 4th.",
          "fact": "arunodaya: prev-night-muhurta-14-15 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during aruṇodaya. It covers 0 of 114 minutes on the 3rd and 113 of 113 on the 4th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one dawn qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 1842 s"
        },
        {
          "step": "ruling",
          "text": "Yama Tarpaṇa, Harbin, 1981: Wednesday 4 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "yama-tarpana",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 14 Yama tarpana (covering a period of 4 ghatikas before sunrise)"
          }
        ],
        "kaala": "arunodaya",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-04",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-04",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Yama Tarpaṇa 1981 falls on Wednesday 4 February. Caturdaśī runs from 07:58 on Tue 3 Feb to 07:23 on Wed 4 Feb and covers all of aruṇodaya that dawn.",
      "cite": "https://ahargana.org/harbin/festivals/1981/yama-tarpana",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ganesha-jayanti",
      "festival": "ganesha-jayanti",
      "name": "Gaṇeśa Jayantī",
      "everyday": "Maghi Ganesh Jayanti",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-08",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 35100,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-02-08T00:20:37+08:00",
          "utc": "1981-02-07T16:20:37Z",
          "ms": 350410836560.28217
        },
        "end": {
          "local": "1981-02-08T21:56:56+08:00",
          "utc": "1981-02-08T13:56:56Z",
          "ms": 350488615853.4666
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-08T00:20:37+08:00",
          "utc": "1981-02-07T16:20:37Z",
          "ms": 350410836560.28217
        },
        "end": {
          "local": "1981-02-08T21:56:56+08:00",
          "utc": "1981-02-08T13:56:56Z",
          "ms": 350488615853.4666
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-02-07",
          "window": {
            "start": {
              "local": "1981-02-07T11:23:52+08:00",
              "utc": "1981-02-07T03:23:52Z",
              "ms": 350364232379.99524
            },
            "end": {
              "local": "1981-02-07T12:11:52+08:00",
              "utc": "1981-02-07T04:11:52Z",
              "ms": 350367112379.99524
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-02-08",
          "window": {
            "start": {
              "local": "1981-02-08T11:23:56+08:00",
              "utc": "1981-02-08T03:23:56Z",
              "ms": 350450635605.1968
            },
            "end": {
              "local": "1981-02-08T12:11:56+08:00",
              "utc": "1981-02-08T04:11:56Z",
              "ms": 350453515605.1968
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 00:21 on Sun 8 Feb to 21:57 on Sun 8 Feb.",
          "fact": "1981-02-07T16:20:37Z → 1981-02-08T13:56:56Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:24–12:12 on the 7th, 11:24–12:12 on the 8th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 0 of 48 minutes on the 7th and 48 of 48 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 35100 s"
        },
        {
          "step": "ruling",
          "text": "Gaṇeśa Jayantī, Harbin, 1981: Sunday 8 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ganesha-jayanti",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 4 Tila caturthi and Kunda caturthi (pradosavyapini), Varada caturthi (Bengal & Orissa), Ganesa caturthi, Ganesa jayanti (madhyahnavyapini purvaviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-08",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-08",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Gaṇeśa Jayantī (Maghi Ganesh Jayanti) 1981 falls on Sunday 8 February. Caturthī runs from 00:21 on Sun 8 Feb to 21:57 on Sun 8 Feb and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ganesha-jayanti",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/tila-chaturthi",
      "festival": "tila-chaturthi",
      "name": "Tila Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-08",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 11796,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-02-08T00:20:37+08:00",
          "utc": "1981-02-07T16:20:37Z",
          "ms": 350410836560.28217
        },
        "end": {
          "local": "1981-02-08T21:56:56+08:00",
          "utc": "1981-02-08T13:56:56Z",
          "ms": 350488615853.4666
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-08T00:20:37+08:00",
          "utc": "1981-02-07T16:20:37Z",
          "ms": 350410836560.28217
        },
        "end": {
          "local": "1981-02-08T21:56:56+08:00",
          "utc": "1981-02-08T13:56:56Z",
          "ms": 350488615853.4666
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-02-07",
          "window": {
            "start": {
              "local": "1981-02-07T16:47:15+08:00",
              "utc": "1981-02-07T08:47:15Z",
              "ms": 350383635012.0071
            },
            "end": {
              "local": "1981-02-07T18:39:14+08:00",
              "utc": "1981-02-07T10:39:14Z",
              "ms": 350390354015.85004
            }
          },
          "covered_min": 0,
          "window_min": 112,
          "qualifies": false
        },
        {
          "local_date": "1981-02-08",
          "window": {
            "start": {
              "local": "1981-02-08T16:48:44+08:00",
              "utc": "1981-02-08T08:48:44Z",
              "ms": 350470123669.5643
            },
            "end": {
              "local": "1981-02-08T18:40:20+08:00",
              "utc": "1981-02-08T10:40:20Z",
              "ms": 350476819682.03564
            }
          },
          "covered_min": 112,
          "window_min": 112,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 00:21 on Sun 8 Feb to 21:57 on Sun 8 Feb.",
          "fact": "1981-02-07T16:20:37Z → 1981-02-08T13:56:56Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:47–18:39 on the 7th, 16:49–18:40 on the 8th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during pradoṣa. It covers 0 of 112 minutes on the 7th and 112 of 112 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 11796 s"
        },
        {
          "step": "ruling",
          "text": "Tila Caturthī, Harbin, 1981: Sunday 8 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "tila-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 4 Tila caturthi and Kunda caturthi (pradosavyapini), Varada caturthi (Bengal & Orissa), Ganesa caturthi, Ganesa jayanti (madhyahnavyapini purvaviddha)."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-08",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-08",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Tila Caturthī 1981 falls on Sunday 8 February. Caturthī runs from 00:21 on Sun 8 Feb to 21:57 on Sun 8 Feb and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/tila-chaturthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shri-panchami",
      "festival": "shri-panchami",
      "name": "Śrī Pañcamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-09",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 26336,
      "anga": {
        "type": "tithi",
        "index": 4,
        "key": "panchami",
        "name": "Pañcamī",
        "start": {
          "local": "1981-02-08T21:56:56+08:00",
          "utc": "1981-02-08T13:56:56Z",
          "ms": 350488615853.4666
        },
        "end": {
          "local": "1981-02-09T19:30:54+08:00",
          "utc": "1981-02-09T11:30:54Z",
          "ms": 350566254077.86145
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-08T21:56:56+08:00",
          "utc": "1981-02-08T13:56:56Z",
          "ms": 350488615853.4666
        },
        "end": {
          "local": "1981-02-09T19:30:54+08:00",
          "utc": "1981-02-09T11:30:54Z",
          "ms": 350566254077.86145
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-02-08",
          "window": {
            "start": {
              "local": "1981-02-08T11:23:56+08:00",
              "utc": "1981-02-08T03:23:56Z",
              "ms": 350450635605.1968
            },
            "end": {
              "local": "1981-02-08T12:11:56+08:00",
              "utc": "1981-02-08T04:11:56Z",
              "ms": 350453515605.1968
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-02-09",
          "window": {
            "start": {
              "local": "1981-02-09T11:23:58+08:00",
              "utc": "1981-02-09T03:23:58Z",
              "ms": 350537038017.66345
            },
            "end": {
              "local": "1981-02-09T12:11:58+08:00",
              "utc": "1981-02-09T04:11:58Z",
              "ms": 350539918017.66345
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pañcamī runs from 21:57 on Sun 8 Feb to 19:31 on Mon 9 Feb.",
          "fact": "1981-02-08T13:56:56Z → 1981-02-09T11:30:54Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:24–12:12 on the 8th, 11:24–12:12 on the 9th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pañcamī must be present during madhyāhna. It covers 0 of 48 minutes on the 8th and 48 of 48 on the 9th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 26336 s"
        },
        {
          "step": "ruling",
          "text": "Śrī Pañcamī, Harbin, 1981: Monday 9 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shri-panchami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 5 Sri Pancami (purvaviddha), Sarasvati puja (Bengal), Vasanta pancami, Madana pancami."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-09",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-09",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śrī Pañcamī 1981 falls on Monday 9 February. Pañcamī runs from 21:57 on Sun 8 Feb to 19:31 on Mon 9 Feb and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shri-panchami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vasanta-panchami",
      "festival": "vasanta-panchami",
      "name": "Vasanta Pañcamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-09",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 26336,
      "anga": {
        "type": "tithi",
        "index": 4,
        "key": "panchami",
        "name": "Pañcamī",
        "start": {
          "local": "1981-02-08T21:56:56+08:00",
          "utc": "1981-02-08T13:56:56Z",
          "ms": 350488615853.4666
        },
        "end": {
          "local": "1981-02-09T19:30:54+08:00",
          "utc": "1981-02-09T11:30:54Z",
          "ms": 350566254077.86145
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-08T21:56:56+08:00",
          "utc": "1981-02-08T13:56:56Z",
          "ms": 350488615853.4666
        },
        "end": {
          "local": "1981-02-09T19:30:54+08:00",
          "utc": "1981-02-09T11:30:54Z",
          "ms": 350566254077.86145
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-02-08",
          "window": {
            "start": {
              "local": "1981-02-08T11:23:56+08:00",
              "utc": "1981-02-08T03:23:56Z",
              "ms": 350450635605.1968
            },
            "end": {
              "local": "1981-02-08T12:11:56+08:00",
              "utc": "1981-02-08T04:11:56Z",
              "ms": 350453515605.1968
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-02-09",
          "window": {
            "start": {
              "local": "1981-02-09T11:23:58+08:00",
              "utc": "1981-02-09T03:23:58Z",
              "ms": 350537038017.66345
            },
            "end": {
              "local": "1981-02-09T12:11:58+08:00",
              "utc": "1981-02-09T04:11:58Z",
              "ms": 350539918017.66345
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pañcamī runs from 21:57 on Sun 8 Feb to 19:31 on Mon 9 Feb.",
          "fact": "1981-02-08T13:56:56Z → 1981-02-09T11:30:54Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:24–12:12 on the 8th, 11:24–12:12 on the 9th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pañcamī must be present during madhyāhna. It covers 0 of 48 minutes on the 8th and 48 of 48 on the 9th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 26336 s"
        },
        {
          "step": "ruling",
          "text": "Vasanta Pañcamī, Harbin, 1981: Monday 9 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vasanta-panchami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 5 Sri Pancami (purvaviddha), Sarasvati puja (Bengal), Vasanta pancami, Madana pancami."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-09",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-09",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vasanta Pañcamī 1981 falls on Monday 9 February. Pañcamī runs from 21:57 on Sun 8 Feb to 19:31 on Mon 9 Feb and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vasanta-panchami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ratha-saptami",
      "festival": "ratha-saptami",
      "name": "Ratha Saptamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 29390,
      "anga": {
        "type": "tithi",
        "index": 6,
        "key": "saptami",
        "name": "Saptamī",
        "start": {
          "local": "1981-02-10T17:07:58+08:00",
          "utc": "1981-02-10T09:07:58Z",
          "ms": 350644077505.1237
        },
        "end": {
          "local": "1981-02-11T14:52:42+08:00",
          "utc": "1981-02-11T06:52:42Z",
          "ms": 350722361753.4865
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-10T17:07:58+08:00",
          "utc": "1981-02-10T09:07:58Z",
          "ms": 350644077505.1237
        },
        "end": {
          "local": "1981-02-11T14:52:42+08:00",
          "utc": "1981-02-11T06:52:42Z",
          "ms": 350722361753.4865
        }
      },
      "kaala": "arunodaya",
      "days": [
        {
          "local_date": "1981-02-10",
          "window": {
            "start": {
              "local": "1981-02-10T04:53:06+08:00",
              "utc": "1981-02-09T20:53:06Z",
              "ms": 350599985629.8174
            },
            "end": {
              "local": "1981-02-10T06:44:18+08:00",
              "utc": "1981-02-09T22:44:18Z",
              "ms": 350606658454.06195
            }
          },
          "covered_min": 0,
          "window_min": 111,
          "qualifies": false
        },
        {
          "local_date": "1981-02-11",
          "window": {
            "start": {
              "local": "1981-02-11T04:52:02+08:00",
              "utc": "1981-02-10T20:52:02Z",
              "ms": 350686322205.36926
            },
            "end": {
              "local": "1981-02-11T06:42:52+08:00",
              "utc": "1981-02-10T22:42:52Z",
              "ms": 350692971654.02277
            }
          },
          "covered_min": 111,
          "window_min": 111,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Saptamī runs from 17:08 on Tue 10 Feb to 14:53 on Wed 11 Feb.",
          "fact": "1981-02-10T09:07:58Z → 1981-02-11T06:52:42Z"
        },
        {
          "step": "kaala",
          "text": "Aruṇodaya is 2 muhūrtas before sunrise: 04:53–06:44 on the 10th, 04:52–06:43 on the 11th.",
          "fact": "arunodaya: prev-night-muhurta-14-15 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Saptamī must be present during aruṇodaya. It covers 0 of 111 minutes on the 10th and 111 of 111 on the 11th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one dawn qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 29390 s"
        },
        {
          "step": "ruling",
          "text": "Ratha Saptamī, Harbin, 1981: Wednesday 11 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ratha-saptami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 7 Ratha saptami (covering 4 ghatikas before sunrise), Acala saptami, Vidhana saptami, Arogya saptami [purvaviddha]."
          }
        ],
        "kaala": "arunodaya",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Ratha Saptamī 1981 falls on Wednesday 11 February. Saptamī runs from 17:08 on Tue 10 Feb to 14:53 on Wed 11 Feb and covers all of aruṇodaya that dawn.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ratha-saptami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-02-15",
      "festival": "ekadashi",
      "name": "Jayā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-15",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 5721,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-02-14T09:26:28+08:00",
          "utc": "1981-02-14T01:26:28Z",
          "ms": 350961987634.47577
        },
        "end": {
          "local": "1981-02-15T08:12:12+08:00",
          "utc": "1981-02-15T00:12:12Z",
          "ms": 351043931757.07263
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-14T09:26:28+08:00",
          "utc": "1981-02-14T01:26:28Z",
          "ms": 350961987634.47577
        },
        "end": {
          "local": "1981-02-15T08:12:12+08:00",
          "utc": "1981-02-15T00:12:12Z",
          "ms": 351043931757.07263
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-02-14",
          "window": {
            "start": {
              "local": "1981-02-14T06:38:23+08:00",
              "utc": "1981-02-13T22:38:23Z",
              "ms": 350951902725.9807
            },
            "end": {
              "local": "1981-02-14T06:38:23+08:00",
              "utc": "1981-02-13T22:38:23Z",
              "ms": 350951902725.9807
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-02-15",
          "window": {
            "start": {
              "local": "1981-02-15T06:36:50+08:00",
              "utc": "1981-02-14T22:36:50Z",
              "ms": 351038210383.49347
            },
            "end": {
              "local": "1981-02-15T06:36:50+08:00",
              "utc": "1981-02-14T22:36:50Z",
              "ms": 351038210383.49347
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 09:26 on Sat 14 Feb to 08:12 on Sun 15 Feb.",
          "fact": "1981-02-14T01:26:28Z → 1981-02-15T00:12:12Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 06:38 on the 14th and 06:37 on the 15th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 14th and is on the 15th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 5721 s"
        },
        {
          "step": "ruling",
          "text": "Jayā Ekādaśī, Harbin, 1981: Sunday 15 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-15",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-15",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Jayā Ekādaśī 1981 falls on Sunday 15 February. Ekādaśī runs from 09:26 on Sat 14 Feb to 08:12 on Sun 15 Feb and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-02-15",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/bhishma-dvadashi",
      "festival": "bhishma-dvadashi",
      "name": "Bhīṣma Dvādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-15",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 11504,
      "anga": {
        "type": "tithi",
        "index": 11,
        "key": "dvadashi",
        "name": "Dvādaśī",
        "start": {
          "local": "1981-02-15T08:12:12+08:00",
          "utc": "1981-02-15T00:12:12Z",
          "ms": 351043931757.07263
        },
        "end": {
          "local": "1981-02-16T07:18:20+08:00",
          "utc": "1981-02-15T23:18:20Z",
          "ms": 351127100008.5359
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-15T08:12:12+08:00",
          "utc": "1981-02-15T00:12:12Z",
          "ms": 351043931757.07263
        },
        "end": {
          "local": "1981-02-16T07:18:20+08:00",
          "utc": "1981-02-15T23:18:20Z",
          "ms": 351127100008.5359
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-02-15",
          "window": {
            "start": {
              "local": "1981-02-15T11:23:56+08:00",
              "utc": "1981-02-15T03:23:56Z",
              "ms": 351055435795.15186
            },
            "end": {
              "local": "1981-02-15T12:11:56+08:00",
              "utc": "1981-02-15T04:11:56Z",
              "ms": 351058315795.15186
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-02-16",
          "window": {
            "start": {
              "local": "1981-02-16T11:23:53+08:00",
              "utc": "1981-02-16T03:23:53Z",
              "ms": 351141832742.3432
            },
            "end": {
              "local": "1981-02-16T12:11:53+08:00",
              "utc": "1981-02-16T04:11:53Z",
              "ms": 351144712742.3432
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvādaśī runs from 08:12 on Sun 15 Feb to 07:18 on Mon 16 Feb.",
          "fact": "1981-02-15T00:12:12Z → 1981-02-15T23:18:20Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:24–12:12 on the 15th, 11:24–12:12 on the 16th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvādaśī must be present during madhyāhna. It covers 48 of 48 minutes on the 15th and 0 of 48 on the 16th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 11504 s"
        },
        {
          "step": "ruling",
          "text": "Bhīṣma Dvādaśī, Harbin, 1981: Sunday 15 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "bhishma-dvadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 12 Bhisma dvadasi (purvaviddha), Amalaki dvadasi, Santana dvadasi, Varaha dvadasi"
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-15",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-15",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Bhīṣma Dvādaśī 1981 falls on Sunday 15 February. Dvādaśī runs from 08:12 on Sun 15 Feb to 07:18 on Mon 16 Feb and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/bhishma-dvadashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-02-16",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 34929,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-02-16T07:18:20+08:00",
          "utc": "1981-02-15T23:18:20Z",
          "ms": 351127100008.5359
        },
        "end": {
          "local": "1981-02-17T06:46:44+08:00",
          "utc": "1981-02-16T22:46:44Z",
          "ms": 351211604178.06757
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-16T07:18:20+08:00",
          "utc": "1981-02-15T23:18:20Z",
          "ms": 351127100008.5359
        },
        "end": {
          "local": "1981-02-17T06:46:44+08:00",
          "utc": "1981-02-16T22:46:44Z",
          "ms": 351211604178.06757
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-02-16",
          "window": {
            "start": {
              "local": "1981-02-16T17:00:29+08:00",
              "utc": "1981-02-16T09:00:29Z",
              "ms": 351162028721.4612
            },
            "end": {
              "local": "1981-02-16T18:48:54+08:00",
              "utc": "1981-02-16T10:48:54Z",
              "ms": 351168534479.7036
            }
          },
          "covered_min": 108,
          "window_min": 108,
          "qualifies": true
        },
        {
          "local_date": "1981-02-17",
          "window": {
            "start": {
              "local": "1981-02-17T17:01:56+08:00",
              "utc": "1981-02-17T09:01:56Z",
              "ms": 351248516014.21674
            },
            "end": {
              "local": "1981-02-17T18:49:57+08:00",
              "utc": "1981-02-17T10:49:57Z",
              "ms": 351254997327.1651
            }
          },
          "covered_min": 0,
          "window_min": 108,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 07:18 on Mon 16 Feb to 06:47 on Tue 17 Feb.",
          "fact": "1981-02-15T23:18:20Z → 1981-02-16T22:46:44Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 17:00–18:49 on the 16th, 17:02–18:50 on the 17th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 108 of 108 minutes on the 16th and 0 of 108 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 34929 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Monday 16 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Monday 16 February. Trayodaśī runs from 07:18 on Mon 16 Feb to 06:47 on Tue 17 Feb and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-02-16",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/maghi-purnima",
      "festival": "maghi-purnima",
      "name": "Māghī Pūrṇimā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-18",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 15925,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-02-18T06:39:23+08:00",
          "utc": "1981-02-17T22:39:23Z",
          "ms": 351297562928.61835
        },
        "end": {
          "local": "1981-02-19T06:58:14+08:00",
          "utc": "1981-02-18T22:58:14Z",
          "ms": 351385093864.15186
        },
        "month": {
          "amanta": 10,
          "purnimanta": 10,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Māgha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-18T06:39:23+08:00",
          "utc": "1981-02-17T22:39:23Z",
          "ms": 351297562928.61835
        },
        "end": {
          "local": "1981-02-19T06:58:14+08:00",
          "utc": "1981-02-18T22:58:14Z",
          "ms": 351385093864.15186
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-02-18",
          "window": {
            "start": {
              "local": "1981-02-18T11:23:44+08:00",
              "utc": "1981-02-18T03:23:44Z",
              "ms": 351314624468.70734
            },
            "end": {
              "local": "1981-02-18T12:11:44+08:00",
              "utc": "1981-02-18T04:11:44Z",
              "ms": 351317504468.70734
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-02-19",
          "window": {
            "start": {
              "local": "1981-02-19T11:23:39+08:00",
              "utc": "1981-02-19T03:23:39Z",
              "ms": 351401019282.20105
            },
            "end": {
              "local": "1981-02-19T12:11:39+08:00",
              "utc": "1981-02-19T04:11:39Z",
              "ms": 351403899282.20105
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 06:39 on Wed 18 Feb to 06:58 on Thu 19 Feb.",
          "fact": "1981-02-17T22:39:23Z → 1981-02-18T22:58:14Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:24–12:12 on the 18th, 11:24–12:12 on the 19th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during madhyāhna. It covers 48 of 48 minutes on the 18th and 0 of 48 on the 19th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 15925 s"
        },
        {
          "step": "ruling",
          "text": "Māghī Pūrṇimā, Harbin, 1981: Wednesday 18 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "maghi-purnima",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Maghi purnima (paraviddha)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-18",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-18",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Māghī Pūrṇimā 1981 falls on Wednesday 18 February. Pūrṇimā runs from 06:39 on Wed 18 Feb to 06:58 on Thu 19 Feb and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/maghi-purnima",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-02-22",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-02-22",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 31438,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-02-22T10:42:16+08:00",
          "utc": "1981-02-22T02:42:16Z",
          "ms": 351657736306.9456
        },
        "end": {
          "local": "1981-02-23T12:48:21+08:00",
          "utc": "1981-02-23T04:48:21Z",
          "ms": 351751701193.31195
        },
        "month": {
          "amanta": 10,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-02-22T10:42:16+08:00",
          "utc": "1981-02-22T02:42:16Z",
          "ms": 351657736306.9456
        },
        "end": {
          "local": "1981-02-23T12:48:21+08:00",
          "utc": "1981-02-23T04:48:21Z",
          "ms": 351751701193.31195
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-02-22",
          "window": {
            "start": {
              "local": "1981-02-22T20:31:52+08:00",
              "utc": "1981-02-22T12:31:52Z",
              "ms": 351693112040.33295
            },
            "end": {
              "local": "1981-02-22T20:31:52+08:00",
              "utc": "1981-02-22T12:31:52Z",
              "ms": 351693112040.33295
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-02-23",
          "window": {
            "start": {
              "local": "1981-02-23T21:32:19+08:00",
              "utc": "1981-02-23T13:32:19Z",
              "ms": 351783138699.14325
            },
            "end": {
              "local": "1981-02-23T21:32:19+08:00",
              "utc": "1981-02-23T13:32:19Z",
              "ms": 351783138699.14325
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 10:42 on Sun 22 Feb to 12:48 on Mon 23 Feb.",
          "fact": "1981-02-22T02:42:16Z → 1981-02-23T04:48:21Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 20:32 on the 22nd and 21:32 on the 23rd.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is on the 22nd and is not on the 23rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 31438 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Sunday 22 February.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-02-22",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-02-22",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Sunday 22 February. Caturthī runs from 10:42 on Sun 22 Feb to 12:48 on Mon 23 Feb and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-02-22",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-03-02",
      "festival": "ekadashi",
      "name": "Vijayā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-02",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 18620,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-03-02T00:48:15+08:00",
          "utc": "1981-03-01T16:48:15Z",
          "ms": 352313295094.4754
        },
        "end": {
          "local": "1981-03-03T00:59:27+08:00",
          "utc": "1981-03-02T16:59:27Z",
          "ms": 352400367270.84766
        },
        "month": {
          "amanta": 10,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-02T00:48:15+08:00",
          "utc": "1981-03-01T16:48:15Z",
          "ms": 352313295094.4754
        },
        "end": {
          "local": "1981-03-03T00:59:27+08:00",
          "utc": "1981-03-02T16:59:27Z",
          "ms": 352400367270.84766
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-03-02",
          "window": {
            "start": {
              "local": "1981-03-02T06:11:35+08:00",
              "utc": "1981-03-01T22:11:35Z",
              "ms": 352332694985.9241
            },
            "end": {
              "local": "1981-03-02T06:11:35+08:00",
              "utc": "1981-03-01T22:11:35Z",
              "ms": 352332694985.9241
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-03-03",
          "window": {
            "start": {
              "local": "1981-03-03T06:09:47+08:00",
              "utc": "1981-03-02T22:09:47Z",
              "ms": 352418987035.3937
            },
            "end": {
              "local": "1981-03-03T06:09:47+08:00",
              "utc": "1981-03-02T22:09:47Z",
              "ms": 352418987035.3937
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 00:48 on Mon 2 Mar to 00:59 on Tue 3 Mar.",
          "fact": "1981-03-01T16:48:15Z → 1981-03-02T16:59:27Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 06:12 on the 2nd and 06:10 on the 3rd.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 2nd and is not on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 18620 s"
        },
        {
          "step": "ruling",
          "text": "Vijayā Ekādaśī, Harbin, 1981: Monday 2 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vijayā Ekādaśī 1981 falls on Monday 2 March. Ekādaśī runs from 00:48 on Mon 2 Mar to 00:59 on Tue 3 Mar and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-03-02",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/maha-shivaratri",
      "festival": "maha-shivaratri",
      "name": "Mahāśivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-04",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1072,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-03-04T23:02:51+08:00",
          "utc": "1981-03-04T15:02:51Z",
          "ms": 352566170737.61273
        },
        "end": {
          "local": "1981-03-05T21:02:48+08:00",
          "utc": "1981-03-05T13:02:48Z",
          "ms": 352645368207.2175
        },
        "month": {
          "amanta": 10,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-04T23:02:51+08:00",
          "utc": "1981-03-04T15:02:51Z",
          "ms": 352566170737.61273
        },
        "end": {
          "local": "1981-03-05T21:02:48+08:00",
          "utc": "1981-03-05T13:02:48Z",
          "ms": 352645368207.2175
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-03-04",
          "window": {
            "start": {
              "local": "1981-03-04T23:20:42+08:00",
              "utc": "1981-03-04T15:20:42Z",
              "ms": 352567242287.5438
            },
            "end": {
              "local": "1981-03-05T00:08:42+08:00",
              "utc": "1981-03-04T16:08:42Z",
              "ms": 352570122287.5438
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-03-05",
          "window": {
            "start": {
              "local": "1981-03-05T23:20:29+08:00",
              "utc": "1981-03-05T15:20:29Z",
              "ms": 352653628965.50525
            },
            "end": {
              "local": "1981-03-06T00:08:29+08:00",
              "utc": "1981-03-05T16:08:29Z",
              "ms": 352656508965.50525
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 23:03 on Wed 4 Mar to 21:03 on Thu 5 Mar.",
          "fact": "1981-03-04T15:02:51Z → 1981-03-05T13:02:48Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:21–00:09 on the 4th, 23:20–00:08 on the 5th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 48 of 48 minutes on the 4th and 0 of 48 on the 5th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: disputed → only-day · margin 1072 s"
        },
        {
          "step": "ruling",
          "text": "Mahāśivarātri, Harbin, 1981: Wednesday 4 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "maha-shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 14 Mahasivaratri (nisithavyapini) — In some opinion it is to be observed on nisitha and in some opinion on pradosa. If occurs on two successive nisithas then according to Hemadri it is to be observed on the first day and according to Madhava, to be observed on the second day"
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "disputed",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-04",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-04",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Mahāśivarātri 1981 falls on Wednesday 4 March. Caturdaśī runs from 23:03 on Wed 4 Mar to 21:03 on Thu 5 Mar and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/maha-shivaratri",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-03-04",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-04",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 14272,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-03-04T00:23:32+08:00",
          "utc": "1981-03-03T16:23:32Z",
          "ms": 352484612003.8966
        },
        "end": {
          "local": "1981-03-04T23:02:51+08:00",
          "utc": "1981-03-04T15:02:51Z",
          "ms": 352566170737.61273
        },
        "month": {
          "amanta": 10,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Māgha",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-04T00:23:32+08:00",
          "utc": "1981-03-03T16:23:32Z",
          "ms": 352484612003.8966
        },
        "end": {
          "local": "1981-03-04T23:02:51+08:00",
          "utc": "1981-03-04T15:02:51Z",
          "ms": 352566170737.61273
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-03-03",
          "window": {
            "start": {
              "local": "1981-03-03T17:21:52+08:00",
              "utc": "1981-03-03T09:21:52Z",
              "ms": 352459311931.0774
            },
            "end": {
              "local": "1981-03-03T19:04:01+08:00",
              "utc": "1981-03-03T11:04:01Z",
              "ms": 352465440796.59045
            }
          },
          "covered_min": 0,
          "window_min": 102,
          "qualifies": false
        },
        {
          "local_date": "1981-03-04",
          "window": {
            "start": {
              "local": "1981-03-04T17:23:15+08:00",
              "utc": "1981-03-04T09:23:15Z",
              "ms": 352545795395.7355
            },
            "end": {
              "local": "1981-03-04T19:04:59+08:00",
              "utc": "1981-03-04T11:04:59Z",
              "ms": 352551898566.8844
            }
          },
          "covered_min": 102,
          "window_min": 102,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 00:24 on Wed 4 Mar to 23:03 on Wed 4 Mar.",
          "fact": "1981-03-03T16:23:32Z → 1981-03-04T15:02:51Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 17:22–19:04 on the 3rd, 17:23–19:05 on the 4th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 102 minutes on the 3rd and 102 of 102 on the 4th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 14272 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Wednesday 4 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-04",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-04",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Wednesday 4 March. Trayodaśī runs from 00:24 on Wed 4 Mar to 23:03 on Wed 4 Mar and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-03-04",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-03-09",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-09",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 7431,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-03-09T09:16:36+08:00",
          "utc": "1981-03-09T01:16:36Z",
          "ms": 352948596335.34644
        },
        "end": {
          "local": "1981-03-10T06:10:27+08:00",
          "utc": "1981-03-09T22:10:27Z",
          "ms": 353023826941.47766
        },
        "month": {
          "amanta": 11,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-09T09:16:36+08:00",
          "utc": "1981-03-09T01:16:36Z",
          "ms": 352948596335.34644
        },
        "end": {
          "local": "1981-03-10T06:10:27+08:00",
          "utc": "1981-03-09T22:10:27Z",
          "ms": 353023826941.47766
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-03-09",
          "window": {
            "start": {
              "local": "1981-03-09T11:20:28+08:00",
              "utc": "1981-03-09T03:20:28Z",
              "ms": 352956027606.9287
            },
            "end": {
              "local": "1981-03-09T12:08:28+08:00",
              "utc": "1981-03-09T04:08:28Z",
              "ms": 352958907606.9287
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-03-10",
          "window": {
            "start": {
              "local": "1981-03-10T11:20:13+08:00",
              "utc": "1981-03-10T03:20:13Z",
              "ms": 353042412563.8312
            },
            "end": {
              "local": "1981-03-10T12:08:13+08:00",
              "utc": "1981-03-10T04:08:13Z",
              "ms": 353045292563.8312
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 09:17 on Mon 9 Mar to 06:10 on Tue 10 Mar.",
          "fact": "1981-03-09T01:16:36Z → 1981-03-09T22:10:27Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:20–12:08 on the 9th, 11:20–12:08 on the 10th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 48 of 48 minutes on the 9th and 0 of 48 on the 10th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 7431 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Monday 9 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-09",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-09",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Monday 9 March. Caturthī runs from 09:17 on Mon 9 Mar to 06:10 on Tue 10 Mar and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-03-09",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-03-16",
      "festival": "ekadashi",
      "name": "Āmalakī Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 36904,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-03-15T19:30:31+08:00",
          "utc": "1981-03-15T11:30:31Z",
          "ms": 353503830509.8775
        },
        "end": {
          "local": "1981-03-16T19:27:17+08:00",
          "utc": "1981-03-16T11:27:17Z",
          "ms": 353590037378.9197
        },
        "month": {
          "amanta": 11,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-15T19:30:31+08:00",
          "utc": "1981-03-15T11:30:31Z",
          "ms": 353503830509.8775
        },
        "end": {
          "local": "1981-03-16T19:27:17+08:00",
          "utc": "1981-03-16T11:27:17Z",
          "ms": 353590037378.9197
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-03-16",
          "window": {
            "start": {
              "local": "1981-03-16T05:45:35+08:00",
              "utc": "1981-03-15T21:45:35Z",
              "ms": 353540734637.5684
            },
            "end": {
              "local": "1981-03-16T05:45:35+08:00",
              "utc": "1981-03-15T21:45:35Z",
              "ms": 353540734637.5684
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-03-17",
          "window": {
            "start": {
              "local": "1981-03-17T05:43:40+08:00",
              "utc": "1981-03-16T21:43:40Z",
              "ms": 353627020237.07794
            },
            "end": {
              "local": "1981-03-17T05:43:40+08:00",
              "utc": "1981-03-16T21:43:40Z",
              "ms": 353627020237.07794
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 19:31 on Sun 15 Mar to 19:27 on Mon 16 Mar.",
          "fact": "1981-03-15T11:30:31Z → 1981-03-16T11:27:17Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 05:46 on the 16th and 05:44 on the 17th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 16th and is not on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 36904 s"
        },
        {
          "step": "ruling",
          "text": "Āmalakī Ekādaśī, Harbin, 1981: Monday 16 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Āmalakī Ekādaśī 1981 falls on Monday 16 March. Ekādaśī runs from 19:31 on Sun 15 Mar to 19:27 on Mon 16 Mar and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-03-16",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-03-18",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-18",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2046,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-03-17T19:51:09+08:00",
          "utc": "1981-03-17T11:51:09Z",
          "ms": 353677868726.4933
        },
        "end": {
          "local": "1981-03-18T20:39:38+08:00",
          "utc": "1981-03-18T12:39:38Z",
          "ms": 353767178202.21246
        },
        "month": {
          "amanta": 11,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-17T19:51:09+08:00",
          "utc": "1981-03-17T11:51:09Z",
          "ms": 353677868726.4933
        },
        "end": {
          "local": "1981-03-18T20:39:38+08:00",
          "utc": "1981-03-18T12:39:38Z",
          "ms": 353767178202.21246
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-03-17",
          "window": {
            "start": {
              "local": "1981-03-17T17:40:56+08:00",
              "utc": "1981-03-17T09:40:56Z",
              "ms": 353670056449.2338
            },
            "end": {
              "local": "1981-03-17T19:17:03+08:00",
              "utc": "1981-03-17T11:17:03Z",
              "ms": 353675823005.13306
            }
          },
          "covered_min": 0,
          "window_min": 96,
          "qualifies": false
        },
        {
          "local_date": "1981-03-18",
          "window": {
            "start": {
              "local": "1981-03-18T17:42:16+08:00",
              "utc": "1981-03-18T09:42:16Z",
              "ms": 353756536395.0107
            },
            "end": {
              "local": "1981-03-18T19:17:57+08:00",
              "utc": "1981-03-18T11:17:57Z",
              "ms": 353762276984.3682
            }
          },
          "covered_min": 96,
          "window_min": 96,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 19:51 on Tue 17 Mar to 20:40 on Wed 18 Mar.",
          "fact": "1981-03-17T11:51:09Z → 1981-03-18T12:39:38Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 17:41–19:17 on the 17th, 17:42–19:18 on the 18th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 96 minutes on the 17th and 96 of 96 on the 18th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 2046 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Wednesday 18 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-18",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-18",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Wednesday 18 March. Trayodaśī runs from 19:51 on Tue 17 Mar to 20:40 on Wed 18 Mar and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-03-18",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/holika-dahana",
      "festival": "holika-dahana",
      "name": "Holikā Dahana",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-20",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 14823,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-03-19T21:50:39+08:00",
          "utc": "1981-03-19T13:50:39Z",
          "ms": 353857838979.0593
        },
        "end": {
          "local": "1981-03-20T23:22:28+08:00",
          "utc": "1981-03-20T15:22:28Z",
          "ms": 353949747999.98016
        },
        "month": {
          "amanta": 11,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-19T21:50:39+08:00",
          "utc": "1981-03-19T13:50:39Z",
          "ms": 353857838979.0593
        },
        "end": {
          "local": "1981-03-20T23:22:28+08:00",
          "utc": "1981-03-20T15:22:28Z",
          "ms": 353949747999.98016
        }
      },
      "kaala": "sayahna",
      "days": [
        {
          "local_date": "1981-03-19",
          "window": {
            "start": {
              "local": "1981-03-19T15:18:51+08:00",
              "utc": "1981-03-19T07:18:51Z",
              "ms": 353834331086.48175
            },
            "end": {
              "local": "1981-03-19T17:43:36+08:00",
              "utc": "1981-03-19T09:43:36Z",
              "ms": 353843016154.30414
            }
          },
          "covered_min": 0,
          "window_min": 145,
          "qualifies": false
        },
        {
          "local_date": "1981-03-20",
          "window": {
            "start": {
              "local": "1981-03-20T15:19:32+08:00",
              "utc": "1981-03-20T07:19:32Z",
              "ms": 353920771765.42126
            },
            "end": {
              "local": "1981-03-20T17:44:56+08:00",
              "utc": "1981-03-20T09:44:56Z",
              "ms": 353929495741.67267
            }
          },
          "covered_min": 145,
          "window_min": 145,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 21:51 on Thu 19 Mar to 23:22 on Fri 20 Mar.",
          "fact": "1981-03-19T13:50:39Z → 1981-03-20T15:22:28Z"
        },
        {
          "step": "kaala",
          "text": "Sāyāhna is last 3 of 15 day muhūrtas: 15:19–17:44 on the 19th, 15:20–17:45 on the 20th.",
          "fact": "sayahna: day-muhurta-13-15 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during sāyāhna. It covers 0 of 145 minutes on the 19th and 145 of 145 on the 20th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one late afternoon qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 14823 s"
        },
        {
          "step": "ruling",
          "text": "Holikā Dahana, Harbin, 1981: Friday 20 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "holika-dahana",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Holika-dahana (Sayahnavyapini — it should be observed on second half of purnima at night), Dolayatra (Bengal & Orissa) (covering 4 ghatikas before sunrise of the day of festival), Holi — on the day after Holikadahana."
          }
        ],
        "not_evaluated": "The hour the row gives for the rite (\"it should be observed on second half of purnima at night\") is not tested: sāyāhna alone settles the day.",
        "kaala": "sayahna",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-20",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-20",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Holikā Dahana 1981 falls on Friday 20 March. Pūrṇimā runs from 21:51 on Thu 19 Mar to 23:22 on Fri 20 Mar and covers all of sāyāhna that late afternoon.",
      "cite": "https://ahargana.org/harbin/festivals/1981/holika-dahana",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/holi",
      "festival": "holi",
      "name": "Holī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-21",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 14823,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-03-19T21:50:39+08:00",
          "utc": "1981-03-19T13:50:39Z",
          "ms": 353857838979.0593
        },
        "end": {
          "local": "1981-03-20T23:22:28+08:00",
          "utc": "1981-03-20T15:22:28Z",
          "ms": 353949747999.98016
        },
        "month": {
          "amanta": 11,
          "purnimanta": 11,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Phālguna"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-19T21:50:39+08:00",
          "utc": "1981-03-19T13:50:39Z",
          "ms": 353857838979.0593
        },
        "end": {
          "local": "1981-03-20T23:22:28+08:00",
          "utc": "1981-03-20T15:22:28Z",
          "ms": 353949747999.98016
        }
      },
      "kaala": "sayahna",
      "days": [
        {
          "local_date": "1981-03-19",
          "window": {
            "start": {
              "local": "1981-03-19T15:18:51+08:00",
              "utc": "1981-03-19T07:18:51Z",
              "ms": 353834331086.48175
            },
            "end": {
              "local": "1981-03-19T17:43:36+08:00",
              "utc": "1981-03-19T09:43:36Z",
              "ms": 353843016154.30414
            }
          },
          "covered_min": 0,
          "window_min": 145,
          "qualifies": false
        },
        {
          "local_date": "1981-03-20",
          "window": {
            "start": {
              "local": "1981-03-20T15:19:32+08:00",
              "utc": "1981-03-20T07:19:32Z",
              "ms": 353920771765.42126
            },
            "end": {
              "local": "1981-03-20T17:44:56+08:00",
              "utc": "1981-03-20T09:44:56Z",
              "ms": 353929495741.67267
            }
          },
          "covered_min": 145,
          "window_min": 145,
          "qualifies": true
        }
      ],
      "follows": {
        "festival": "holika-dahana",
        "name": "Holikā Dahana",
        "local_date": "1981-03-20",
        "days": 1
      },
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 21:51 on Thu 19 Mar to 23:22 on Fri 20 Mar.",
          "fact": "1981-03-19T13:50:39Z → 1981-03-20T15:22:28Z"
        },
        {
          "step": "kaala",
          "text": "Sāyāhna is last 3 of 15 day muhūrtas: 15:19–17:44 on the 19th, 15:20–17:45 on the 20th.",
          "fact": "sayahna: day-muhurta-13-15 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during sāyāhna. It covers 0 of 145 minutes on the 19th and 145 of 145 on the 20th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one late afternoon qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 14823 s"
        },
        {
          "step": "counted",
          "text": "Holī is kept the day after Holikā Dahana: Friday 20 March is the day taken above.",
          "fact": "follows: holika-dahana + 1 d"
        },
        {
          "step": "ruling",
          "text": "Holī, Harbin, 1981: Saturday 21 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "holi",
        "follows": {
          "festival": "holika-dahana",
          "days": 1
        },
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Holika-dahana (Sayahnavyapini — it should be observed on second half of purnima at night), Dolayatra (Bengal & Orissa) (covering 4 ghatikas before sunrise of the day of festival), Holi — on the day after Holikadahana."
          }
        ],
        "kaala": "sayahna",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-21",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-21",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Holī 1981 falls on Saturday 21 March. It is kept the day after Holikā Dahana, which falls on Friday 20 March. Pūrṇimā runs from 21:51 on Thu 19 Mar to 23:22 on Fri 20 Mar and covers all of sāyāhna on the 20th.",
      "cite": "https://ahargana.org/harbin/festivals/1981/holi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vasantotsava",
      "festival": "vasantotsava",
      "name": "Vasantotsava",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-21",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 15639,
      "anga": {
        "type": "tithi",
        "index": 15,
        "key": "pratipada",
        "name": "Pratipadā",
        "start": {
          "local": "1981-03-20T23:22:28+08:00",
          "utc": "1981-03-20T15:22:28Z",
          "ms": 353949747999.98016
        },
        "end": {
          "local": "1981-03-22T01:13:27+08:00",
          "utc": "1981-03-21T17:13:27Z",
          "ms": 354042806818.16345
        },
        "month": {
          "amanta": 11,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-20T23:22:28+08:00",
          "utc": "1981-03-20T15:22:28Z",
          "ms": 353949747999.98016
        },
        "end": {
          "local": "1981-03-22T01:13:27+08:00",
          "utc": "1981-03-21T17:13:27Z",
          "ms": 354042806818.16345
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-03-21",
          "window": {
            "start": {
              "local": "1981-03-21T05:36:01+08:00",
              "utc": "1981-03-20T21:36:01Z",
              "ms": 353972160787.09106
            },
            "end": {
              "local": "1981-03-21T05:36:01+08:00",
              "utc": "1981-03-20T21:36:01Z",
              "ms": 353972160787.09106
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-03-22",
          "window": {
            "start": {
              "local": "1981-03-22T05:34:06+08:00",
              "utc": "1981-03-21T21:34:06Z",
              "ms": 354058445627.933
            },
            "end": {
              "local": "1981-03-22T05:34:06+08:00",
              "utc": "1981-03-21T21:34:06Z",
              "ms": 354058445627.933
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pratipadā runs from 23:22 on Fri 20 Mar to 01:13 on Sun 22 Mar.",
          "fact": "1981-03-20T15:22:28Z → 1981-03-21T17:13:27Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 05:36 on the 21st and 05:34 on the 22nd.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pratipadā must be current at sunrise. It is on the 21st and is not on the 22nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 15639 s"
        },
        {
          "step": "ruling",
          "text": "Vasantotsava, Harbin, 1981: Saturday 21 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vasantotsava",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 1 Vasantotsava (current at sunrise, if occurs on two successive days, it is to be observed on the first day)."
          }
        ],
        "kaala": "sunrise",
        "priority": "purvaviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-21",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-21",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vasantotsava 1981 falls on Saturday 21 March. Pratipadā runs from 23:22 on Fri 20 Mar to 01:13 on Sun 22 Mar and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vasantotsava",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-03-24",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-24",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 33621,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-03-24T05:42:38+08:00",
          "utc": "1981-03-23T21:42:38Z",
          "ms": 354231758106.3136
        },
        "end": {
          "local": "1981-03-25T08:11:27+08:00",
          "utc": "1981-03-25T00:11:27Z",
          "ms": 354327086796.3051
        },
        "month": {
          "amanta": 11,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-24T05:42:38+08:00",
          "utc": "1981-03-23T21:42:38Z",
          "ms": 354231758106.3136
        },
        "end": {
          "local": "1981-03-25T08:11:27+08:00",
          "utc": "1981-03-25T00:11:27Z",
          "ms": 354327086796.3051
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-03-23",
          "window": {
            "start": {
              "local": "1981-03-23T20:22:17+08:00",
              "utc": "1981-03-23T12:22:17Z",
              "ms": 354198136673.0629
            },
            "end": {
              "local": "1981-03-23T20:22:17+08:00",
              "utc": "1981-03-23T12:22:17Z",
              "ms": 354198136673.0629
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-03-24",
          "window": {
            "start": {
              "local": "1981-03-24T21:22:16+08:00",
              "utc": "1981-03-24T13:22:16Z",
              "ms": 354288136186.8585
            },
            "end": {
              "local": "1981-03-24T21:22:16+08:00",
              "utc": "1981-03-24T13:22:16Z",
              "ms": 354288136186.8585
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 05:43 on Tue 24 Mar to 08:11 on Wed 25 Mar.",
          "fact": "1981-03-23T21:42:38Z → 1981-03-25T00:11:27Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 20:22 on the 23rd and 21:22 on the 24th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is not on the 23rd and is on the 24th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 33621 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Tuesday 24 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-24",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-24",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Tuesday 24 March. Caturthī runs from 05:43 on Tue 24 Mar to 08:11 on Wed 25 Mar and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-03-24",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shitalashtami",
      "festival": "shitalashtami",
      "name": "Śītalāṣṭamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-03-29",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 9996,
      "anga": {
        "type": "tithi",
        "index": 22,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-03-28T14:49:37+08:00",
          "utc": "1981-03-28T06:49:37Z",
          "ms": 354610177460.78845
        },
        "end": {
          "local": "1981-03-29T16:08:33+08:00",
          "utc": "1981-03-29T08:08:33Z",
          "ms": 354701313181.9542
        },
        "month": {
          "amanta": 11,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-28T14:49:37+08:00",
          "utc": "1981-03-28T06:49:37Z",
          "ms": 354610177460.78845
        },
        "end": {
          "local": "1981-03-29T16:08:33+08:00",
          "utc": "1981-03-29T08:08:33Z",
          "ms": 354701313181.9542
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-03-28",
          "window": {
            "start": {
              "local": "1981-03-28T11:15:01+08:00",
              "utc": "1981-03-28T03:15:01Z",
              "ms": 354597301313.274
            },
            "end": {
              "local": "1981-03-28T12:03:01+08:00",
              "utc": "1981-03-28T04:03:01Z",
              "ms": 354600181313.274
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-03-29",
          "window": {
            "start": {
              "local": "1981-03-29T11:14:43+08:00",
              "utc": "1981-03-29T03:14:43Z",
              "ms": 354683683210.3279
            },
            "end": {
              "local": "1981-03-29T12:02:43+08:00",
              "utc": "1981-03-29T04:02:43Z",
              "ms": 354686563210.3279
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 14:50 on Sat 28 Mar to 16:09 on Sun 29 Mar.",
          "fact": "1981-03-28T06:49:37Z → 1981-03-29T08:08:33Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:15–12:03 on the 28th, 11:15–12:03 on the 29th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be present during madhyāhna. It covers 0 of 48 minutes on the 28th and 48 of 48 on the 29th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 9996 s"
        },
        {
          "step": "ruling",
          "text": "Śītalāṣṭamī, Harbin, 1981: Sunday 29 March.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shitalashtami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 8 Sitalastami, (purvaviddha)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-03-29",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-03-29",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śītalāṣṭamī 1981 falls on Sunday 29 March. Aṣṭamī runs from 14:50 on Sat 28 Mar to 16:09 on Sun 29 Mar and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shitalashtami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-04-01",
      "festival": "ekadashi",
      "name": "Pāpamocanī Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-01",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 36617,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-03-31T16:29:48+08:00",
          "utc": "1981-03-31T08:29:48Z",
          "ms": 354875388241.33105
        },
        "end": {
          "local": "1981-04-01T15:25:13+08:00",
          "utc": "1981-04-01T07:25:13Z",
          "ms": 354957913396.8219
        },
        "month": {
          "amanta": 11,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-03-31T16:29:48+08:00",
          "utc": "1981-03-31T08:29:48Z",
          "ms": 354875388241.33105
        },
        "end": {
          "local": "1981-04-01T15:25:13+08:00",
          "utc": "1981-04-01T07:25:13Z",
          "ms": 354957913396.8219
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-03-31",
          "window": {
            "start": {
              "local": "1981-03-31T05:16:51+08:00",
              "utc": "1981-03-30T21:16:51Z",
              "ms": 354835010626.66846
            },
            "end": {
              "local": "1981-03-31T05:16:51+08:00",
              "utc": "1981-03-30T21:16:51Z",
              "ms": 354835010626.66846
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-04-01",
          "window": {
            "start": {
              "local": "1981-04-01T05:14:56+08:00",
              "utc": "1981-03-31T21:14:56Z",
              "ms": 354921296362.68097
            },
            "end": {
              "local": "1981-04-01T05:14:56+08:00",
              "utc": "1981-03-31T21:14:56Z",
              "ms": 354921296362.68097
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 16:30 on Tue 31 Mar to 15:25 on Wed 1 Apr.",
          "fact": "1981-03-31T08:29:48Z → 1981-04-01T07:25:13Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 05:17 on the 31st and 05:15 on the 1st.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 31st and is on the 1st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 36617 s"
        },
        {
          "step": "ruling",
          "text": "Pāpamocanī Ekādaśī, Harbin, 1981: Wednesday 1 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-01",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-01",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Pāpamocanī Ekādaśī 1981 falls on Wednesday 1 April. Ekādaśī runs from 16:30 on Tue 31 Mar to 15:25 on Wed 1 Apr and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-04-01",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-04-02",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-02",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 16157,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-04-02T13:32:43+08:00",
          "utc": "1981-04-02T05:32:43Z",
          "ms": 355037563482.32886
        },
        "end": {
          "local": "1981-04-03T10:58:20+08:00",
          "utc": "1981-04-03T02:58:20Z",
          "ms": 355114699891.5753
        },
        "month": {
          "amanta": 11,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-02T13:32:43+08:00",
          "utc": "1981-04-02T05:32:43Z",
          "ms": 355037563482.32886
        },
        "end": {
          "local": "1981-04-03T10:58:20+08:00",
          "utc": "1981-04-03T02:58:20Z",
          "ms": 355114699891.5753
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-04-02",
          "window": {
            "start": {
              "local": "1981-04-02T18:02:01+08:00",
              "utc": "1981-04-02T10:02:01Z",
              "ms": 355053720828.0313
            },
            "end": {
              "local": "1981-04-02T19:31:14+08:00",
              "utc": "1981-04-02T11:31:14Z",
              "ms": 355059073870.1272
            }
          },
          "covered_min": 89,
          "window_min": 89,
          "qualifies": true
        },
        {
          "local_date": "1981-04-03",
          "window": {
            "start": {
              "local": "1981-04-03T18:03:19+08:00",
              "utc": "1981-04-03T10:03:19Z",
              "ms": 355140199309.29974
            },
            "end": {
              "local": "1981-04-03T19:32:07+08:00",
              "utc": "1981-04-03T11:32:07Z",
              "ms": 355145526767.61426
            }
          },
          "covered_min": 0,
          "window_min": 89,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 13:33 on Thu 2 Apr to 10:58 on Fri 3 Apr.",
          "fact": "1981-04-02T05:32:43Z → 1981-04-03T02:58:20Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:02–19:31 on the 2nd, 18:03–19:32 on the 3rd.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 89 of 89 minutes on the 2nd and 0 of 89 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 16157 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Thursday 2 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Thursday 2 April. Trayodaśī runs from 13:33 on Thu 2 Apr to 10:58 on Fri 3 Apr and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-04-02",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-04-03",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-03",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 28215,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-04-03T10:58:20+08:00",
          "utc": "1981-04-03T02:58:20Z",
          "ms": 355114699891.5753
        },
        "end": {
          "local": "1981-04-04T07:50:32+08:00",
          "utc": "1981-04-03T23:50:32Z",
          "ms": 355189832140.00006
        },
        "month": {
          "amanta": 11,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Phālguna",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-03T10:58:20+08:00",
          "utc": "1981-04-03T02:58:20Z",
          "ms": 355114699891.5753
        },
        "end": {
          "local": "1981-04-04T07:50:32+08:00",
          "utc": "1981-04-03T23:50:32Z",
          "ms": 355189832140.00006
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-04-02",
          "window": {
            "start": {
              "local": "1981-04-02T23:12:35+08:00",
              "utc": "1981-04-02T15:12:35Z",
              "ms": 355072354735.89075
            },
            "end": {
              "local": "1981-04-03T00:00:35+08:00",
              "utc": "1981-04-02T16:00:35Z",
              "ms": 355075234735.89075
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-04-03",
          "window": {
            "start": {
              "local": "1981-04-03T23:12:17+08:00",
              "utc": "1981-04-03T15:12:17Z",
              "ms": 355158737277.9791
            },
            "end": {
              "local": "1981-04-04T00:00:17+08:00",
              "utc": "1981-04-03T16:00:17Z",
              "ms": 355161617277.9791
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 10:58 on Fri 3 Apr to 07:51 on Sat 4 Apr.",
          "fact": "1981-04-03T02:58:20Z → 1981-04-03T23:50:32Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:13–00:01 on the 2nd, 23:12–00:00 on the 3rd.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 0 of 48 minutes on the 2nd and 48 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 28215 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Friday 3 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-03",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-03",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Friday 3 April. Caturdaśī runs from 10:58 on Fri 3 Apr to 07:51 on Sat 4 Apr and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-04-03",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/navaratra-arambha-caitra",
      "festival": "navaratra-arambha-caitra",
      "name": "Navarātrārambha (Caitra)",
      "everyday": "Chaitra Navratri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-05",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 24793,
      "anga": {
        "type": "tithi",
        "index": 0,
        "key": "pratipada",
        "name": "Pratipadā",
        "start": {
          "local": "1981-04-05T04:19:26+08:00",
          "utc": "1981-04-04T20:19:26Z",
          "ms": 355263566231.01166
        },
        "end": {
          "local": "1981-04-06T00:36:01+08:00",
          "utc": "1981-04-05T16:36:01Z",
          "ms": 355336560631.19214
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-05T04:19:26+08:00",
          "utc": "1981-04-04T20:19:26Z",
          "ms": 355263566231.01166
        },
        "end": {
          "local": "1981-04-06T00:36:01+08:00",
          "utc": "1981-04-05T16:36:01Z",
          "ms": 355336560631.19214
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-05",
          "window": {
            "start": {
              "local": "1981-04-05T11:12:39+08:00",
              "utc": "1981-04-05T03:12:39Z",
              "ms": 355288359196.5228
            },
            "end": {
              "local": "1981-04-05T12:00:39+08:00",
              "utc": "1981-04-05T04:00:39Z",
              "ms": 355291239196.5228
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-04-06",
          "window": {
            "start": {
              "local": "1981-04-06T11:12:22+08:00",
              "utc": "1981-04-06T03:12:22Z",
              "ms": 355374742060.306
            },
            "end": {
              "local": "1981-04-06T12:00:22+08:00",
              "utc": "1981-04-06T04:00:22Z",
              "ms": 355377622060.306
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pratipadā runs from 04:19 on Sun 5 Apr to 00:36 on Mon 6 Apr.",
          "fact": "1981-04-04T20:19:26Z → 1981-04-05T16:36:01Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:13–12:01 on the 5th, 11:12–12:00 on the 6th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pratipadā must be present during madhyāhna. It covers 48 of 48 minutes on the 5th and 0 of 48 on the 6th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 24793 s"
        },
        {
          "step": "ruling",
          "text": "Navarātrārambha (Caitra), Harbin, 1981: Sunday 5 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "navaratra-arambha-caitra",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 1 Navaratrarambha (paraviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-05",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-05",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Navarātrārambha (Caitra) (Chaitra Navratri) 1981 falls on Sunday 5 April. Pratipadā runs from 04:19 on Sun 5 Apr to 00:36 on Mon 6 Apr and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/navaratra-arambha-caitra",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/gauri-tritiya",
      "festival": "gauri-tritiya",
      "name": "Gaurī Tṛtīyā",
      "everyday": "Gangaur",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-07",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 19009,
      "anga": {
        "type": "tithi",
        "index": 2,
        "key": "tritiya",
        "name": "Tṛtīyā",
        "start": {
          "local": "1981-04-06T20:51:30+08:00",
          "utc": "1981-04-06T12:51:30Z",
          "ms": 355409490112.8974
        },
        "end": {
          "local": "1981-04-07T17:16:54+08:00",
          "utc": "1981-04-07T09:16:54Z",
          "ms": 355483014351.7101
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-06T20:51:30+08:00",
          "utc": "1981-04-06T12:51:30Z",
          "ms": 355409490112.8974
        },
        "end": {
          "local": "1981-04-07T17:16:54+08:00",
          "utc": "1981-04-07T09:16:54Z",
          "ms": 355483014351.7101
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-06",
          "window": {
            "start": {
              "local": "1981-04-06T11:12:22+08:00",
              "utc": "1981-04-06T03:12:22Z",
              "ms": 355374742060.306
            },
            "end": {
              "local": "1981-04-06T12:00:22+08:00",
              "utc": "1981-04-06T04:00:22Z",
              "ms": 355377622060.306
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-04-07",
          "window": {
            "start": {
              "local": "1981-04-07T11:12:05+08:00",
              "utc": "1981-04-07T03:12:05Z",
              "ms": 355461125110.49097
            },
            "end": {
              "local": "1981-04-07T12:00:05+08:00",
              "utc": "1981-04-07T04:00:05Z",
              "ms": 355464005110.49097
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Tṛtīyā runs from 20:52 on Mon 6 Apr to 17:17 on Tue 7 Apr.",
          "fact": "1981-04-06T12:51:30Z → 1981-04-07T09:16:54Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:12–12:00 on the 6th, 11:12–12:00 on the 7th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Tṛtīyā must be present during madhyāhna. It covers 0 of 48 minutes on the 6th and 48 of 48 on the 7th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 19009 s"
        },
        {
          "step": "ruling",
          "text": "Gaurī Tṛtīyā, Harbin, 1981: Tuesday 7 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "gauri-tritiya",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 3 Dolotsava, Gauri trtiya, Andolana trtiya, Saubhagya sayana vrata (paraviddha), Sarhul (Bihar)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-07",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-07",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Gaurī Tṛtīyā (Gangaur) 1981 falls on Tuesday 7 April. Tṛtīyā runs from 20:52 on Mon 6 Apr to 17:17 on Tue 7 Apr and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/gauri-tritiya",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/saubhagya-shayana-vrata",
      "festival": "saubhagya-shayana-vrata",
      "name": "Saubhāgya Śayana Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-07",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 19009,
      "anga": {
        "type": "tithi",
        "index": 2,
        "key": "tritiya",
        "name": "Tṛtīyā",
        "start": {
          "local": "1981-04-06T20:51:30+08:00",
          "utc": "1981-04-06T12:51:30Z",
          "ms": 355409490112.8974
        },
        "end": {
          "local": "1981-04-07T17:16:54+08:00",
          "utc": "1981-04-07T09:16:54Z",
          "ms": 355483014351.7101
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-06T20:51:30+08:00",
          "utc": "1981-04-06T12:51:30Z",
          "ms": 355409490112.8974
        },
        "end": {
          "local": "1981-04-07T17:16:54+08:00",
          "utc": "1981-04-07T09:16:54Z",
          "ms": 355483014351.7101
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-06",
          "window": {
            "start": {
              "local": "1981-04-06T11:12:22+08:00",
              "utc": "1981-04-06T03:12:22Z",
              "ms": 355374742060.306
            },
            "end": {
              "local": "1981-04-06T12:00:22+08:00",
              "utc": "1981-04-06T04:00:22Z",
              "ms": 355377622060.306
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-04-07",
          "window": {
            "start": {
              "local": "1981-04-07T11:12:05+08:00",
              "utc": "1981-04-07T03:12:05Z",
              "ms": 355461125110.49097
            },
            "end": {
              "local": "1981-04-07T12:00:05+08:00",
              "utc": "1981-04-07T04:00:05Z",
              "ms": 355464005110.49097
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Tṛtīyā runs from 20:52 on Mon 6 Apr to 17:17 on Tue 7 Apr.",
          "fact": "1981-04-06T12:51:30Z → 1981-04-07T09:16:54Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:12–12:00 on the 6th, 11:12–12:00 on the 7th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Tṛtīyā must be present during madhyāhna. It covers 0 of 48 minutes on the 6th and 48 of 48 on the 7th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 19009 s"
        },
        {
          "step": "ruling",
          "text": "Saubhāgya Śayana Vrata, Harbin, 1981: Tuesday 7 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "saubhagya-shayana-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 3 Dolotsava, Gauri trtiya, Andolana trtiya, Saubhagya sayana vrata (paraviddha), Sarhul (Bihar)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-07",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-07",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saubhāgya Śayana Vrata 1981 falls on Tuesday 7 April. Tṛtīyā runs from 20:52 on Mon 6 Apr to 17:17 on Tue 7 Apr and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/saubhagya-shayana-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-04-08",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-08",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 7359,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-04-07T17:16:54+08:00",
          "utc": "1981-04-07T09:16:54Z",
          "ms": 355483014351.7101
        },
        "end": {
          "local": "1981-04-08T14:02:27+08:00",
          "utc": "1981-04-08T06:02:27Z",
          "ms": 355557747224.876
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-07T17:16:54+08:00",
          "utc": "1981-04-07T09:16:54Z",
          "ms": 355483014351.7101
        },
        "end": {
          "local": "1981-04-08T14:02:27+08:00",
          "utc": "1981-04-08T06:02:27Z",
          "ms": 355557747224.876
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-07",
          "window": {
            "start": {
              "local": "1981-04-07T11:12:05+08:00",
              "utc": "1981-04-07T03:12:05Z",
              "ms": 355461125110.49097
            },
            "end": {
              "local": "1981-04-07T12:00:05+08:00",
              "utc": "1981-04-07T04:00:05Z",
              "ms": 355464005110.49097
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-04-08",
          "window": {
            "start": {
              "local": "1981-04-08T11:11:48+08:00",
              "utc": "1981-04-08T03:11:48Z",
              "ms": 355547508360.18726
            },
            "end": {
              "local": "1981-04-08T11:59:48+08:00",
              "utc": "1981-04-08T03:59:48Z",
              "ms": 355550388360.18726
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 17:17 on Tue 7 Apr to 14:02 on Wed 8 Apr.",
          "fact": "1981-04-07T09:16:54Z → 1981-04-08T06:02:27Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:12–12:00 on the 7th, 11:12–12:00 on the 8th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 0 of 48 minutes on the 7th and 48 of 48 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 7359 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Wednesday 8 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-08",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-08",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Wednesday 8 April. Caturthī runs from 17:17 on Tue 7 Apr to 14:02 on Wed 8 Apr and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-04-08",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/lakshmi-panchami",
      "festival": "lakshmi-panchami",
      "name": "Lakṣmī Pañcamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-09",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 332,
      "anga": {
        "type": "tithi",
        "index": 4,
        "key": "panchami",
        "name": "Pañcamī",
        "start": {
          "local": "1981-04-08T14:02:27+08:00",
          "utc": "1981-04-08T06:02:27Z",
          "ms": 355557747224.876
        },
        "end": {
          "local": "1981-04-09T11:17:04+08:00",
          "utc": "1981-04-09T03:17:04Z",
          "ms": 355634223802.0378
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-08T14:02:27+08:00",
          "utc": "1981-04-08T06:02:27Z",
          "ms": 355557747224.876
        },
        "end": {
          "local": "1981-04-09T11:17:04+08:00",
          "utc": "1981-04-09T03:17:04Z",
          "ms": 355634223802.0378
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-08",
          "window": {
            "start": {
              "local": "1981-04-08T11:11:48+08:00",
              "utc": "1981-04-08T03:11:48Z",
              "ms": 355547508360.18726
            },
            "end": {
              "local": "1981-04-08T11:59:48+08:00",
              "utc": "1981-04-08T03:59:48Z",
              "ms": 355550388360.18726
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-04-09",
          "window": {
            "start": {
              "local": "1981-04-09T11:11:32+08:00",
              "utc": "1981-04-09T03:11:32Z",
              "ms": 355633891823.23193
            },
            "end": {
              "local": "1981-04-09T11:59:32+08:00",
              "utc": "1981-04-09T03:59:32Z",
              "ms": 355636771823.23193
            }
          },
          "covered_min": 6,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pañcamī runs from 14:02 on Wed 8 Apr to 11:17 on Thu 9 Apr.",
          "fact": "1981-04-08T06:02:27Z → 1981-04-09T03:17:04Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:12–12:00 on the 8th, 11:12–12:00 on the 9th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pañcamī must be present during madhyāhna. It covers 0 of 48 minutes on the 8th and 6 of 48 on the 9th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 332 s"
        },
        {
          "step": "ruling",
          "text": "Lakṣmī Pañcamī, Harbin, 1981: Thursday 9 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "lakshmi-panchami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 5 Sri pancami or Laksmi pancami (purvaviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-09",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-09",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Lakṣmī Pañcamī 1981 falls on Thursday 9 April. Pañcamī runs from 14:02 on Wed 8 Apr to 11:17 on Thu 9 Apr and covers 6 of 48 minutes of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/lakshmi-panchami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/bhavani-utpatti",
      "festival": "bhavani-utpatti",
      "name": "Bhavānī Utpatti",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 12717,
      "anga": {
        "type": "tithi",
        "index": 7,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-04-11T07:39:03+08:00",
          "utc": "1981-04-10T23:39:03Z",
          "ms": 355793942644.5259
        },
        "end": {
          "local": "1981-04-12T06:52:37+08:00",
          "utc": "1981-04-11T22:52:37Z",
          "ms": 355877557146.43115
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-11T07:39:03+08:00",
          "utc": "1981-04-10T23:39:03Z",
          "ms": 355793942644.5259
        },
        "end": {
          "local": "1981-04-12T06:52:37+08:00",
          "utc": "1981-04-11T22:52:37Z",
          "ms": 355877557146.43115
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-11",
          "window": {
            "start": {
              "local": "1981-04-11T11:10:59+08:00",
              "utc": "1981-04-11T03:10:59Z",
              "ms": 355806659449.6487
            },
            "end": {
              "local": "1981-04-11T11:58:59+08:00",
              "utc": "1981-04-11T03:58:59Z",
              "ms": 355809539449.6487
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-04-12",
          "window": {
            "start": {
              "local": "1981-04-12T11:10:44+08:00",
              "utc": "1981-04-12T03:10:44Z",
              "ms": 355893043645.5209
            },
            "end": {
              "local": "1981-04-12T11:58:44+08:00",
              "utc": "1981-04-12T03:58:44Z",
              "ms": 355895923645.5209
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 07:39 on Sat 11 Apr to 06:53 on Sun 12 Apr.",
          "fact": "1981-04-10T23:39:03Z → 1981-04-11T22:52:37Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:11–11:59 on the 11th, 11:11–11:59 on the 12th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be present during madhyāhna. It covers 48 of 48 minutes on the 11th and 0 of 48 on the 12th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 12717 s"
        },
        {
          "step": "ruling",
          "text": "Bhavānī Utpatti, Harbin, 1981: Saturday 11 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "bhavani-utpatti",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 8 Annapurna puja (Beng.) (paraviddha), Bhavani-utpatti (paraviddha), Asokastami (Special when combined with naks. Punarvasu and Wednesday, after mid-day)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Bhavānī Utpatti 1981 falls on Saturday 11 April. Aṣṭamī runs from 07:39 on Sat 11 Apr to 06:53 on Sun 12 Apr and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/bhavani-utpatti",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/rama-navami",
      "festival": "rama-navami",
      "name": "Rāma Navamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-12",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 15486,
      "anga": {
        "type": "tithi",
        "index": 8,
        "key": "navami",
        "name": "Navamī",
        "start": {
          "local": "1981-04-12T06:52:37+08:00",
          "utc": "1981-04-11T22:52:37Z",
          "ms": 355877557146.43115
        },
        "end": {
          "local": "1981-04-13T06:47:12+08:00",
          "utc": "1981-04-12T22:47:12Z",
          "ms": 355963632028.60504
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-12T06:52:37+08:00",
          "utc": "1981-04-11T22:52:37Z",
          "ms": 355877557146.43115
        },
        "end": {
          "local": "1981-04-13T06:47:12+08:00",
          "utc": "1981-04-12T22:47:12Z",
          "ms": 355963632028.60504
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-12",
          "window": {
            "start": {
              "local": "1981-04-12T11:10:44+08:00",
              "utc": "1981-04-12T03:10:44Z",
              "ms": 355893043645.5209
            },
            "end": {
              "local": "1981-04-12T11:58:44+08:00",
              "utc": "1981-04-12T03:58:44Z",
              "ms": 355895923645.5209
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-04-13",
          "window": {
            "start": {
              "local": "1981-04-13T11:10:28+08:00",
              "utc": "1981-04-13T03:10:28Z",
              "ms": 355979428119.3557
            },
            "end": {
              "local": "1981-04-13T11:58:28+08:00",
              "utc": "1981-04-13T03:58:28Z",
              "ms": 355982308119.3557
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Navamī runs from 06:53 on Sun 12 Apr to 06:47 on Mon 13 Apr.",
          "fact": "1981-04-11T22:52:37Z → 1981-04-12T22:47:12Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:11–11:59 on the 12th, 11:10–11:58 on the 13th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Navamī must be present during madhyāhna. It covers 48 of 48 minutes on the 12th and 0 of 48 on the 13th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 15486 s"
        },
        {
          "step": "ruling",
          "text": "Rāma Navamī, Harbin, 1981: Sunday 12 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "rama-navami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 9 Ramanavami (madhyahnavyapini, special with Punarvasu naks.), Rama jayanti."
          }
        ],
        "not_evaluated": "The row calls the day special when it falls with Punarvasu nakṣatra; the nakṣatra is not tested.",
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-12",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-12",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Rāma Navamī 1981 falls on Sunday 12 April. Navamī runs from 06:53 on Sun 12 Apr to 06:47 on Mon 13 Apr and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/rama-navami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vaishakhi",
      "festival": "vaishakhi",
      "name": "Vaiśākhī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-13",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 21094,
      "anga": {
        "type": "sankranti",
        "index": 0,
        "key": "mesha",
        "name": "Meṣa",
        "start": {
          "local": "1981-04-13T22:59:11+08:00",
          "utc": "1981-04-13T14:59:11Z",
          "ms": 356021951172.8104
        },
        "end": {
          "local": "1981-05-14T19:56:40+08:00",
          "utc": "1981-05-14T11:56:40Z",
          "ms": 358689399806.40643
        }
      },
      "span": {
        "of": "transit",
        "start": {
          "local": "1981-04-13T22:59:11+08:00",
          "utc": "1981-04-13T14:59:11Z",
          "ms": 356021951172.8104
        },
        "end": {
          "local": "1981-04-13T22:59:11+08:00",
          "utc": "1981-04-13T14:59:11Z",
          "ms": 356021951172.8104
        }
      },
      "kaala": "day",
      "days": [
        {
          "local_date": "1981-04-13",
          "window": {
            "start": {
              "local": "1981-04-13T04:52:34+08:00",
              "utc": "1981-04-12T20:52:34Z",
              "ms": 355956753669.0506
            },
            "end": {
              "local": "1981-04-14T04:50:45+08:00",
              "utc": "1981-04-13T20:50:45Z",
              "ms": 356043045059.6401
            }
          },
          "covered_min": 1,
          "window_min": 1438,
          "qualifies": true
        },
        {
          "local_date": "1981-04-14",
          "window": {
            "start": {
              "local": "1981-04-14T04:50:45+08:00",
              "utc": "1981-04-13T20:50:45Z",
              "ms": 356043045059.6401
            },
            "end": {
              "local": "1981-04-15T04:48:57+08:00",
              "utc": "1981-04-14T20:48:57Z",
              "ms": 356129337108.4177
            }
          },
          "covered_min": 0,
          "window_min": 1438,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "The Sun enters Meṣa at 22:59 on Mon 13 Apr.",
          "fact": "1981-04-13T14:59:11Z · nirayana, lahiri-iae1985"
        },
        {
          "step": "kaala",
          "text": "The day runs from sunrise to the next sunrise: from 04:53 on the 13th, and from 04:51 on the 14th.",
          "fact": "day: sunrise-to-sunrise · sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "The festival is kept on the day of the transit, the day counted from sunrise. The transit falls on the 13th, not the 14th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 106"
        },
        {
          "step": "tie_break",
          "text": "An instant falls in one day and no other. No tie-break is needed.",
          "fact": "day counted from sunrise → only-day · margin 21094 s"
        },
        {
          "step": "ruling",
          "text": "Vaiśākhī, Harbin, 1981: Monday 13 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "solar",
        "id": "vaishakhi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Mesadi — Cadaka puja (Bengal), Bahag Bihu (Assam), Cheiraoba (Manipur), Visu (T. C. State), Vaisakhi (on the samkramana day commencing from sunrise)."
          },
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The following festivals are observed according to the day of Sun's transit into rasis (Ravi-samkramana). For this purpose the day has been taken to begin from midnight, i.e., when the samkramana takes place after midnight, the festival relating to the samkramana is to be observed on the following day."
          }
        ],
        "not_evaluated": "The other names in the row (Cadaka puja, Bahag Bihu, Cheiraoba, Visu) are regional observances and wait with the regional rows.",
        "rashi": "Meṣa",
        "day_from": "sunrise"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-13",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-13",
          "confidence": "determinate"
        },
        {
          "kind": "reckoning",
          "id": "civil-day",
          "local_date": "1981-04-13",
          "statement": "Counted from midnight",
          "reference": {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 106",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The following festivals are observed according to the day of Sun's transit into rasis (Ravi-samkramana). For this purpose the day has been taken to begin from midnight, i.e., when the samkramana takes place after midnight, the festival relating to the samkramana is to be observed on the following day."
          }
        },
        {
          "kind": "reckoning",
          "id": "sunset-rule",
          "local_date": "1981-04-14",
          "statement": "Past sunset, the next day (the Tamil rule)",
          "reference": {
            "text": "Calendar Reform Committee 1955, Rules of Samkranti",
            "locator": "p. 244",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The Tamil rule: In the Tamil districts the rule is that when a samkranti takes place before sunset, the month begins on the same day, while if it takes place after sunset the month begins on the following day."
          }
        }
      ],
      "quote": "In Harbin, Vaiśākhī 1981 falls on Monday 13 April. The Sun enters Meṣa at 22:59 on Mon 13 Apr, and the rule counts the day from sunrise. By the Tamil rule for the first day of a solar month, which gives a transit after sunset to the next day, it is 14 April.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vaishakhi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-04-15",
      "festival": "ekadashi",
      "name": "Kāmadā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-15",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 8894,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-04-14T07:18:59+08:00",
          "utc": "1981-04-13T23:18:59Z",
          "ms": 356051939030.2655
        },
        "end": {
          "local": "1981-04-15T08:22:28+08:00",
          "utc": "1981-04-15T00:22:28Z",
          "ms": 356142148387.1143
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-14T07:18:59+08:00",
          "utc": "1981-04-13T23:18:59Z",
          "ms": 356051939030.2655
        },
        "end": {
          "local": "1981-04-15T08:22:28+08:00",
          "utc": "1981-04-15T00:22:28Z",
          "ms": 356142148387.1143
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-04-14",
          "window": {
            "start": {
              "local": "1981-04-14T04:50:45+08:00",
              "utc": "1981-04-13T20:50:45Z",
              "ms": 356043045059.6401
            },
            "end": {
              "local": "1981-04-14T04:50:45+08:00",
              "utc": "1981-04-13T20:50:45Z",
              "ms": 356043045059.6401
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-04-15",
          "window": {
            "start": {
              "local": "1981-04-15T04:48:57+08:00",
              "utc": "1981-04-14T20:48:57Z",
              "ms": 356129337108.4177
            },
            "end": {
              "local": "1981-04-15T04:48:57+08:00",
              "utc": "1981-04-14T20:48:57Z",
              "ms": 356129337108.4177
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 07:19 on Tue 14 Apr to 08:22 on Wed 15 Apr.",
          "fact": "1981-04-13T23:18:59Z → 1981-04-15T00:22:28Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 04:51 on the 14th and 04:49 on the 15th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 14th and is on the 15th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 8894 s"
        },
        {
          "step": "ruling",
          "text": "Kāmadā Ekādaśī, Harbin, 1981: Wednesday 15 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-15",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-15",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kāmadā Ekādaśī 1981 falls on Wednesday 15 April. Ekādaśī runs from 07:19 on Tue 14 Apr to 08:22 on Wed 15 Apr and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-04-15",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ananga-trayodashi",
      "festival": "ananga-trayodashi",
      "name": "Anaṅga Trayodaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1024,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-04-16T09:51:33+08:00",
          "utc": "1981-04-16T01:51:33Z",
          "ms": 356233892714.3723
        },
        "end": {
          "local": "1981-04-17T11:40:25+08:00",
          "utc": "1981-04-17T03:40:25Z",
          "ms": 356326824734.34015
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-16T09:51:33+08:00",
          "utc": "1981-04-16T01:51:33Z",
          "ms": 356233892714.3723
        },
        "end": {
          "local": "1981-04-17T11:40:25+08:00",
          "utc": "1981-04-17T03:40:25Z",
          "ms": 356326824734.34015
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-16",
          "window": {
            "start": {
              "local": "1981-04-16T11:09:43+08:00",
              "utc": "1981-04-16T03:09:43Z",
              "ms": 356238583386.21875
            },
            "end": {
              "local": "1981-04-16T11:57:43+08:00",
              "utc": "1981-04-16T03:57:43Z",
              "ms": 356241463386.21875
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-04-17",
          "window": {
            "start": {
              "local": "1981-04-17T11:09:29+08:00",
              "utc": "1981-04-17T03:09:29Z",
              "ms": 356324969149.79987
            },
            "end": {
              "local": "1981-04-17T11:57:29+08:00",
              "utc": "1981-04-17T03:57:29Z",
              "ms": 356327849149.79987
            }
          },
          "covered_min": 31,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "purvaviddha",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 09:52 on Thu 16 Apr to 11:40 on Fri 17 Apr.",
          "fact": "1981-04-16T01:51:33Z → 1981-04-17T03:40:25Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:10–11:58 on the 16th, 11:09–11:57 on the 17th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during madhyāhna. It covers 48 of 48 minutes on the 16th and 31 of 48 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Both middays qualify. Pūrvaviddhā: the first is taken.",
          "fact": "priority: purvaviddha → purvaviddha · margin 1024 s"
        },
        {
          "step": "ruling",
          "text": "Anaṅga Trayodaśī, Harbin, 1981: Thursday 16 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ananga-trayodashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 13 Ananga trayodasi (purvaviddha), Mahavira jayanti (Jain)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Anaṅga Trayodaśī 1981 falls on Thursday 16 April. Trayodaśī runs from 09:52 on Thu 16 Apr to 11:40 on Fri 17 Apr and covers all of madhyāhna that midday. It also reaches the next midday for 31 minutes; by the rule the first midday is taken.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ananga-trayodashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-04-16",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 24070,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-04-16T09:51:33+08:00",
          "utc": "1981-04-16T01:51:33Z",
          "ms": 356233892714.3723
        },
        "end": {
          "local": "1981-04-17T11:40:25+08:00",
          "utc": "1981-04-17T03:40:25Z",
          "ms": 356326824734.34015
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-16T09:51:33+08:00",
          "utc": "1981-04-16T01:51:33Z",
          "ms": 356233892714.3723
        },
        "end": {
          "local": "1981-04-17T11:40:25+08:00",
          "utc": "1981-04-17T03:40:25Z",
          "ms": 356326824734.34015
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-04-16",
          "window": {
            "start": {
              "local": "1981-04-16T18:20:17+08:00",
              "utc": "1981-04-16T10:20:17Z",
              "ms": 356264416922.11035
            },
            "end": {
              "local": "1981-04-16T19:43:38+08:00",
              "utc": "1981-04-16T11:43:38Z",
              "ms": 356269417775.2331
            }
          },
          "covered_min": 83,
          "window_min": 83,
          "qualifies": true
        },
        {
          "local_date": "1981-04-17",
          "window": {
            "start": {
              "local": "1981-04-17T18:21:35+08:00",
              "utc": "1981-04-17T10:21:35Z",
              "ms": 356350894979.06866
            },
            "end": {
              "local": "1981-04-17T19:44:31+08:00",
              "utc": "1981-04-17T11:44:31Z",
              "ms": 356355871322.4444
            }
          },
          "covered_min": 0,
          "window_min": 83,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 09:52 on Thu 16 Apr to 11:40 on Fri 17 Apr.",
          "fact": "1981-04-16T01:51:33Z → 1981-04-17T03:40:25Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:20–19:44 on the 16th, 18:22–19:45 on the 17th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 83 of 83 minutes on the 16th and 0 of 83 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 24070 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Thursday 16 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Thursday 16 April. Trayodaśī runs from 09:52 on Thu 16 Apr to 11:40 on Fri 17 Apr and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-04-16",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vishnu-damanaka-chaturdashi",
      "festival": "vishnu-damanaka-chaturdashi",
      "name": "Viṣṇudamanaka Caturdaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-18",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1024,
      "anga": {
        "type": "tithi",
        "index": 13,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-04-17T11:40:25+08:00",
          "utc": "1981-04-17T03:40:25Z",
          "ms": 356326824734.34015
        },
        "end": {
          "local": "1981-04-18T13:44:11+08:00",
          "utc": "1981-04-18T05:44:11Z",
          "ms": 356420651273.18164
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-17T11:40:25+08:00",
          "utc": "1981-04-17T03:40:25Z",
          "ms": 356326824734.34015
        },
        "end": {
          "local": "1981-04-18T13:44:11+08:00",
          "utc": "1981-04-18T05:44:11Z",
          "ms": 356420651273.18164
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-17",
          "window": {
            "start": {
              "local": "1981-04-17T11:09:29+08:00",
              "utc": "1981-04-17T03:09:29Z",
              "ms": 356324969149.79987
            },
            "end": {
              "local": "1981-04-17T11:57:29+08:00",
              "utc": "1981-04-17T03:57:29Z",
              "ms": 356327849149.79987
            }
          },
          "covered_min": 17,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-04-18",
          "window": {
            "start": {
              "local": "1981-04-18T11:09:15+08:00",
              "utc": "1981-04-18T03:09:15Z",
              "ms": 356411355280.1074
            },
            "end": {
              "local": "1981-04-18T11:57:15+08:00",
              "utc": "1981-04-18T03:57:15Z",
              "ms": 356414235280.1074
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "paraviddha",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 11:40 on Fri 17 Apr to 13:44 on Sat 18 Apr.",
          "fact": "1981-04-17T03:40:25Z → 1981-04-18T05:44:11Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:09–11:57 on the 17th, 11:09–11:57 on the 18th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during madhyāhna. It covers 17 of 48 minutes on the 17th and 48 of 48 on the 18th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Both middays qualify. Paraviddhā: the second is taken.",
          "fact": "priority: paraviddha → paraviddha · margin 1024 s"
        },
        {
          "step": "ruling",
          "text": "Viṣṇudamanaka Caturdaśī, Harbin, 1981: Saturday 18 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vishnu-damanaka-chaturdashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 14 Madanabhanji, (Bengal & Orissa) (paraviddha), Sivadamanaka caturdasi, Visnudamanaka caturdasi (paraviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-18",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-18",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Viṣṇudamanaka Caturdaśī 1981 falls on Saturday 18 April. Caturdaśī runs from 11:40 on Fri 17 Apr to 13:44 on Sat 18 Apr and covers all of madhyāhna that midday. It also reaches the previous midday for 17 minutes; by the rule the second midday is taken.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vishnu-damanaka-chaturdashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/chaitri-purnima",
      "festival": "chaitri-purnima",
      "name": "Caitrī Pūrṇimā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-19",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 6416,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-04-18T13:44:11+08:00",
          "utc": "1981-04-18T05:44:11Z",
          "ms": 356420651273.18164
        },
        "end": {
          "local": "1981-04-19T15:58:55+08:00",
          "utc": "1981-04-19T07:58:55Z",
          "ms": 356515135072.7287
        },
        "month": {
          "amanta": 0,
          "purnimanta": 0,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Caitra"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-18T13:44:11+08:00",
          "utc": "1981-04-18T05:44:11Z",
          "ms": 356420651273.18164
        },
        "end": {
          "local": "1981-04-19T15:58:55+08:00",
          "utc": "1981-04-19T07:58:55Z",
          "ms": 356515135072.7287
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-04-18",
          "window": {
            "start": {
              "local": "1981-04-18T11:09:15+08:00",
              "utc": "1981-04-18T03:09:15Z",
              "ms": 356411355280.1074
            },
            "end": {
              "local": "1981-04-18T11:57:15+08:00",
              "utc": "1981-04-18T03:57:15Z",
              "ms": 356414235280.1074
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-04-19",
          "window": {
            "start": {
              "local": "1981-04-19T11:09:02+08:00",
              "utc": "1981-04-19T03:09:02Z",
              "ms": 356497741794.3369
            },
            "end": {
              "local": "1981-04-19T11:57:02+08:00",
              "utc": "1981-04-19T03:57:02Z",
              "ms": 356500621794.3369
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 13:44 on Sat 18 Apr to 15:59 on Sun 19 Apr.",
          "fact": "1981-04-18T05:44:11Z → 1981-04-19T07:58:55Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:09–11:57 on the 18th, 11:09–11:57 on the 19th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during madhyāhna. It covers 0 of 48 minutes on the 18th and 48 of 48 on the 19th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 6416 s"
        },
        {
          "step": "ruling",
          "text": "Caitrī Pūrṇimā, Harbin, 1981: Sunday 19 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "chaitri-purnima",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Caitri purnima (paraviddha), Hanumat jayanti, Oli ending (Jain)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-19",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-19",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Caitrī Pūrṇimā 1981 falls on Sunday 19 April. Pūrṇimā runs from 13:44 on Sat 18 Apr to 15:59 on Sun 19 Apr and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/chaitri-purnima",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-04-23",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-23",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 7059,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-04-22T23:11:32+08:00",
          "utc": "1981-04-22T15:11:32Z",
          "ms": 356800292237.0658
        },
        "end": {
          "local": "1981-04-24T01:28:08+08:00",
          "utc": "1981-04-23T17:28:08Z",
          "ms": 356894887726.6423
        },
        "month": {
          "amanta": 0,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-22T23:11:32+08:00",
          "utc": "1981-04-22T15:11:32Z",
          "ms": 356800292237.0658
        },
        "end": {
          "local": "1981-04-24T01:28:08+08:00",
          "utc": "1981-04-23T17:28:08Z",
          "ms": 356894887726.6423
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-04-22",
          "window": {
            "start": {
              "local": "1981-04-22T21:13:53+08:00",
              "utc": "1981-04-22T13:13:53Z",
              "ms": 356793233406.5476
            },
            "end": {
              "local": "1981-04-22T21:13:53+08:00",
              "utc": "1981-04-22T13:13:53Z",
              "ms": 356793233406.5476
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-04-23",
          "window": {
            "start": {
              "local": "1981-04-23T22:11:36+08:00",
              "utc": "1981-04-23T14:11:36Z",
              "ms": 356883096063.3362
            },
            "end": {
              "local": "1981-04-23T22:11:36+08:00",
              "utc": "1981-04-23T14:11:36Z",
              "ms": 356883096063.3362
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 23:12 on Wed 22 Apr to 01:28 on Fri 24 Apr.",
          "fact": "1981-04-22T15:11:32Z → 1981-04-23T17:28:08Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 21:14 on the 22nd and 22:12 on the 23rd.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is not on the 22nd and is on the 23rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 7059 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Thursday 23 April.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-23",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-23",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Thursday 23 April. Caturthī runs from 23:12 on Wed 22 Apr to 01:28 on Fri 24 Apr and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-04-23",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-04-30",
      "festival": "ekadashi",
      "name": "Varūthinī Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-04-30",
      "confidence": "boundary",
      "boundary_reasons": [
        "margin"
      ],
      "boundary_margin_s": 154,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-04-30T04:21:07+08:00",
          "utc": "1981-04-29T20:21:07Z",
          "ms": 357423667048.8556
        },
        "end": {
          "local": "1981-05-01T02:12:06+08:00",
          "utc": "1981-04-30T18:12:06Z",
          "ms": 357502326242.0843
        },
        "month": {
          "amanta": 0,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-04-30T04:21:07+08:00",
          "utc": "1981-04-29T20:21:07Z",
          "ms": 357423667048.8556
        },
        "end": {
          "local": "1981-05-01T02:12:06+08:00",
          "utc": "1981-04-30T18:12:06Z",
          "ms": 357502326242.0843
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-04-30",
          "window": {
            "start": {
              "local": "1981-04-30T04:23:41+08:00",
              "utc": "1981-04-29T20:23:41Z",
              "ms": 357423821051.1135
            },
            "end": {
              "local": "1981-04-30T04:23:41+08:00",
              "utc": "1981-04-29T20:23:41Z",
              "ms": 357423821051.1135
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-05-01",
          "window": {
            "start": {
              "local": "1981-05-01T04:22:09+08:00",
              "utc": "1981-04-30T20:22:09Z",
              "ms": 357510128508.99347
            },
            "end": {
              "local": "1981-05-01T04:22:09+08:00",
              "utc": "1981-04-30T20:22:09Z",
              "ms": 357510128508.99347
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 04:21 on Thu 30 Apr to 02:12 on Fri 1 May.",
          "fact": "1981-04-29T20:21:07Z → 1981-04-30T18:12:06Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 04:24 on the 30th and 04:22 on the 1st.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 30th and is not on the 1st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 154 s < 300 s"
        },
        {
          "step": "ruling",
          "text": "Varūthinī Ekādaśī, Harbin, 1981: Thursday 30 April.",
          "fact": "confidence: boundary (margin)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-04-30",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-04-30",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Varūthinī Ekādaśī 1981 falls on Thursday 30 April. Ekādaśī runs from 04:21 on Thu 30 Apr to 02:12 on Fri 1 May and is current at sunrise that day. It is 2 min 34 s from a threshold: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-04-30",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-05-02",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-02",
      "confidence": "boundary",
      "boundary_reasons": [
        "margin"
      ],
      "boundary_margin_s": 108,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-05-01T23:22:13+08:00",
          "utc": "1981-05-01T15:22:13Z",
          "ms": 357578533320.6456
        },
        "end": {
          "local": "1981-05-02T19:59:52+08:00",
          "utc": "1981-05-02T11:59:52Z",
          "ms": 357652791784.8772
        },
        "month": {
          "amanta": 0,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-01T23:22:13+08:00",
          "utc": "1981-05-01T15:22:13Z",
          "ms": 357578533320.6456
        },
        "end": {
          "local": "1981-05-02T19:59:52+08:00",
          "utc": "1981-05-02T11:59:52Z",
          "ms": 357652791784.8772
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-05-01",
          "window": {
            "start": {
              "local": "1981-05-01T18:39:42+08:00",
              "utc": "1981-05-01T10:39:42Z",
              "ms": 357561582178.1456
            },
            "end": {
              "local": "1981-05-01T19:57:10+08:00",
              "utc": "1981-05-01T11:57:10Z",
              "ms": 357566229519.5414
            }
          },
          "covered_min": 0,
          "window_min": 77,
          "qualifies": false
        },
        {
          "local_date": "1981-05-02",
          "window": {
            "start": {
              "local": "1981-05-02T18:40:59+08:00",
              "utc": "1981-05-02T10:40:59Z",
              "ms": 357648058978.3931
            },
            "end": {
              "local": "1981-05-02T19:58:04+08:00",
              "utc": "1981-05-02T11:58:04Z",
              "ms": 357652684084.5361
            }
          },
          "covered_min": 77,
          "window_min": 77,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 23:22 on Fri 1 May to 20:00 on Sat 2 May.",
          "fact": "1981-05-01T15:22:13Z → 1981-05-02T11:59:52Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:40–19:57 on the 1st, 18:41–19:58 on the 2nd.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 77 minutes on the 1st and 77 of 77 on the 2nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 108 s < 300 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Saturday 2 May.",
          "fact": "confidence: boundary (margin)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Saturday 2 May. Trayodaśī runs from 23:22 on Fri 1 May to 20:00 on Sat 2 May and covers all of pradoṣa that evening. It is 1 min 48 s from a threshold: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-05-02",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-05-02",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-02",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 11171,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-05-02T19:59:52+08:00",
          "utc": "1981-05-02T11:59:52Z",
          "ms": 357652791784.8772
        },
        "end": {
          "local": "1981-05-03T16:15:08+08:00",
          "utc": "1981-05-03T08:15:08Z",
          "ms": 357725708258.6358
        },
        "month": {
          "amanta": 0,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Caitra",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-02T19:59:52+08:00",
          "utc": "1981-05-02T11:59:52Z",
          "ms": 357652791784.8772
        },
        "end": {
          "local": "1981-05-03T16:15:08+08:00",
          "utc": "1981-05-03T08:15:08Z",
          "ms": 357725708258.6358
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-05-02",
          "window": {
            "start": {
              "local": "1981-05-02T23:06:03+08:00",
              "utc": "1981-05-02T15:06:03Z",
              "ms": 357663963126.4292
            },
            "end": {
              "local": "1981-05-02T23:54:03+08:00",
              "utc": "1981-05-02T15:54:03Z",
              "ms": 357666843126.4292
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-05-03",
          "window": {
            "start": {
              "local": "1981-05-03T23:05:57+08:00",
              "utc": "1981-05-03T15:05:57Z",
              "ms": 357750357102.5231
            },
            "end": {
              "local": "1981-05-03T23:53:57+08:00",
              "utc": "1981-05-03T15:53:57Z",
              "ms": 357753237102.5231
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 20:00 on Sat 2 May to 16:15 on Sun 3 May.",
          "fact": "1981-05-02T11:59:52Z → 1981-05-03T08:15:08Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:06–23:54 on the 2nd, 23:06–23:54 on the 3rd.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 48 of 48 minutes on the 2nd and 0 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 11171 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Saturday 2 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Saturday 2 May. Caturdaśī runs from 20:00 on Sat 2 May to 16:15 on Sun 3 May and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-05-02",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/akshaya-tritiya",
      "festival": "akshaya-tritiya",
      "name": "Akṣaya Tṛtīyā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-06",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1491,
      "anga": {
        "type": "tithi",
        "index": 2,
        "key": "tritiya",
        "name": "Tṛtīyā",
        "start": {
          "local": "1981-05-06T04:39:36+08:00",
          "utc": "1981-05-05T20:39:36Z",
          "ms": 357943176116.2125
        },
        "end": {
          "local": "1981-05-07T01:18:19+08:00",
          "utc": "1981-05-06T17:18:19Z",
          "ms": 358017499447.8388
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-06T04:39:36+08:00",
          "utc": "1981-05-05T20:39:36Z",
          "ms": 357943176116.2125
        },
        "end": {
          "local": "1981-05-07T01:18:19+08:00",
          "utc": "1981-05-06T17:18:19Z",
          "ms": 358017499447.8388
        }
      },
      "kaala": "purvahna",
      "days": [
        {
          "local_date": "1981-05-06",
          "window": {
            "start": {
              "local": "1981-05-06T04:14:46+08:00",
              "utc": "1981-05-05T20:14:46Z",
              "ms": 357941685551.13684
            },
            "end": {
              "local": "1981-05-06T09:05:12+08:00",
              "utc": "1981-05-06T01:05:12Z",
              "ms": 357959111574.08575
            }
          },
          "covered_min": 266,
          "window_min": 290,
          "qualifies": true
        },
        {
          "local_date": "1981-05-07",
          "window": {
            "start": {
              "local": "1981-05-07T04:13:21+08:00",
              "utc": "1981-05-06T20:13:21Z",
              "ms": 358028001143.59326
            },
            "end": {
              "local": "1981-05-07T09:04:40+08:00",
              "utc": "1981-05-07T01:04:40Z",
              "ms": 358045480418.67267
            }
          },
          "covered_min": 0,
          "window_min": 291,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Tṛtīyā runs from 04:40 on Wed 6 May to 01:18 on Thu 7 May.",
          "fact": "1981-05-05T20:39:36Z → 1981-05-06T17:18:19Z"
        },
        {
          "step": "kaala",
          "text": "Pūrvāhṇa is first 5 of 15 day muhūrtas: 04:15–09:05 on the 6th, 04:13–09:05 on the 7th.",
          "fact": "purvahna: day-muhurta-1-5 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Tṛtīyā must be present during pūrvāhṇa. It covers 266 of 290 minutes on the 6th and 0 of 291 on the 7th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one forenoon qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 1491 s"
        },
        {
          "step": "ruling",
          "text": "Akṣaya Tṛtīyā, Harbin, 1981: Wednesday 6 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "akshaya-tritiya",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 3 Aksaya trtiya (purvahna vyapini, paraviddha) (Special when combined with Rohini naksatra and Wednesday), Candanayatra, Parasurama jayanti (pradosavyapini — if occurs on two successive days, the second day is to be observed)."
          }
        ],
        "not_evaluated": "The row calls the day special with Rohiṇī nakṣatra and a Wednesday; neither is tested.",
        "kaala": "purvahna",
        "priority": "paraviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-06",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-06",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Akṣaya Tṛtīyā 1981 falls on Wednesday 6 May. Tṛtīyā runs from 04:40 on Wed 6 May to 01:18 on Thu 7 May and covers 266 of 290 minutes of pūrvāhṇa that forenoon.",
      "cite": "https://ahargana.org/harbin/festivals/1981/akshaya-tritiya",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/parashurama-jayanti",
      "festival": "parashurama-jayanti",
      "name": "Paraśurāma Jayantī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-06",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 18997,
      "anga": {
        "type": "tithi",
        "index": 2,
        "key": "tritiya",
        "name": "Tṛtīyā",
        "start": {
          "local": "1981-05-06T04:39:36+08:00",
          "utc": "1981-05-05T20:39:36Z",
          "ms": 357943176116.2125
        },
        "end": {
          "local": "1981-05-07T01:18:19+08:00",
          "utc": "1981-05-06T17:18:19Z",
          "ms": 358017499447.8388
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-06T04:39:36+08:00",
          "utc": "1981-05-05T20:39:36Z",
          "ms": 357943176116.2125
        },
        "end": {
          "local": "1981-05-07T01:18:19+08:00",
          "utc": "1981-05-06T17:18:19Z",
          "ms": 358017499447.8388
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-05-05",
          "window": {
            "start": {
              "local": "1981-05-05T18:44:48+08:00",
              "utc": "1981-05-05T10:44:48Z",
              "ms": 357907487910.48645
            },
            "end": {
              "local": "1981-05-05T20:00:48+08:00",
              "utc": "1981-05-05T12:00:48Z",
              "ms": 357912047595.9065
            }
          },
          "covered_min": 0,
          "window_min": 76,
          "qualifies": false
        },
        {
          "local_date": "1981-05-06",
          "window": {
            "start": {
              "local": "1981-05-06T18:46:04+08:00",
              "utc": "1981-05-06T10:46:04Z",
              "ms": 357993963619.98364
            },
            "end": {
              "local": "1981-05-06T20:01:42+08:00",
              "utc": "1981-05-06T12:01:42Z",
              "ms": 357998501956.4649
            }
          },
          "covered_min": 76,
          "window_min": 76,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Tṛtīyā runs from 04:40 on Wed 6 May to 01:18 on Thu 7 May.",
          "fact": "1981-05-05T20:39:36Z → 1981-05-06T17:18:19Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:45–20:01 on the 5th, 18:46–20:02 on the 6th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Tṛtīyā must be present during pradoṣa. It covers 0 of 76 minutes on the 5th and 76 of 76 on the 6th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 18997 s"
        },
        {
          "step": "ruling",
          "text": "Paraśurāma Jayantī, Harbin, 1981: Wednesday 6 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "parashurama-jayanti",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 3 Aksaya trtiya (purvahna vyapini, paraviddha) (Special when combined with Rohini naksatra and Wednesday), Candanayatra, Parasurama jayanti (pradosavyapini — if occurs on two successive days, the second day is to be observed)."
          }
        ],
        "kaala": "pradosha",
        "priority": "paraviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-06",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-06",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Paraśurāma Jayantī 1981 falls on Wednesday 6 May. Tṛtīyā runs from 04:40 on Wed 6 May to 01:18 on Thu 7 May and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/parashurama-jayanti",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-05-07",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-07",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 35281,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-05-07T01:18:19+08:00",
          "utc": "1981-05-06T17:18:19Z",
          "ms": 358017499447.8388
        },
        "end": {
          "local": "1981-05-07T22:29:22+08:00",
          "utc": "1981-05-07T14:29:22Z",
          "ms": 358093762151.16986
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-07T01:18:19+08:00",
          "utc": "1981-05-06T17:18:19Z",
          "ms": 358017499447.8388
        },
        "end": {
          "local": "1981-05-07T22:29:22+08:00",
          "utc": "1981-05-07T14:29:22Z",
          "ms": 358093762151.16986
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-05-07",
          "window": {
            "start": {
              "local": "1981-05-07T11:06:20+08:00",
              "utc": "1981-05-07T03:06:20Z",
              "ms": 358052780056.2124
            },
            "end": {
              "local": "1981-05-07T11:54:20+08:00",
              "utc": "1981-05-07T03:54:20Z",
              "ms": 358055660056.2124
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-05-08",
          "window": {
            "start": {
              "local": "1981-05-08T11:06:16+08:00",
              "utc": "1981-05-08T03:06:16Z",
              "ms": 358139176065.0657
            },
            "end": {
              "local": "1981-05-08T11:54:16+08:00",
              "utc": "1981-05-08T03:54:16Z",
              "ms": 358142056065.0657
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 01:18 on Thu 7 May to 22:29 on Thu 7 May.",
          "fact": "1981-05-06T17:18:19Z → 1981-05-07T14:29:22Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:06–11:54 on the 7th, 11:06–11:54 on the 8th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 48 of 48 minutes on the 7th and 0 of 48 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 35281 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Thursday 7 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-07",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-07",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Thursday 7 May. Caturthī runs from 01:18 on Thu 7 May to 22:29 on Thu 7 May and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-05-07",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shankara-jayanti",
      "festival": "shankara-jayanti",
      "name": "Śaṅkara Jayantī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-08",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 30381,
      "anga": {
        "type": "tithi",
        "index": 4,
        "key": "panchami",
        "name": "Pañcamī",
        "start": {
          "local": "1981-05-07T22:29:22+08:00",
          "utc": "1981-05-07T14:29:22Z",
          "ms": 358093762151.16986
        },
        "end": {
          "local": "1981-05-08T20:20:37+08:00",
          "utc": "1981-05-08T12:20:37Z",
          "ms": 358172436836.14996
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-07T22:29:22+08:00",
          "utc": "1981-05-07T14:29:22Z",
          "ms": 358093762151.16986
        },
        "end": {
          "local": "1981-05-08T20:20:37+08:00",
          "utc": "1981-05-08T12:20:37Z",
          "ms": 358172436836.14996
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-05-07",
          "window": {
            "start": {
              "local": "1981-05-07T11:06:20+08:00",
              "utc": "1981-05-07T03:06:20Z",
              "ms": 358052780056.2124
            },
            "end": {
              "local": "1981-05-07T11:54:20+08:00",
              "utc": "1981-05-07T03:54:20Z",
              "ms": 358055660056.2124
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-05-08",
          "window": {
            "start": {
              "local": "1981-05-08T11:06:16+08:00",
              "utc": "1981-05-08T03:06:16Z",
              "ms": 358139176065.0657
            },
            "end": {
              "local": "1981-05-08T11:54:16+08:00",
              "utc": "1981-05-08T03:54:16Z",
              "ms": 358142056065.0657
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pañcamī runs from 22:29 on Thu 7 May to 20:21 on Fri 8 May.",
          "fact": "1981-05-07T14:29:22Z → 1981-05-08T12:20:37Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:06–11:54 on the 7th, 11:06–11:54 on the 8th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pañcamī must be present during madhyāhna. It covers 0 of 48 minutes on the 7th and 48 of 48 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 30381 s"
        },
        {
          "step": "ruling",
          "text": "Śaṅkara Jayantī, Harbin, 1981: Friday 8 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shankara-jayanti",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 5 Sankara jayanti."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-08",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-08",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śaṅkara Jayantī 1981 falls on Friday 8 May. Pañcamī runs from 22:29 on Thu 7 May to 20:21 on Fri 8 May and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shankara-jayanti",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/gangotpatti",
      "festival": "gangotpatti",
      "name": "Gaṅgotpatti",
      "everyday": "Ganga Saptami",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-10",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 23266,
      "anga": {
        "type": "tithi",
        "index": 6,
        "key": "saptami",
        "name": "Saptamī",
        "start": {
          "local": "1981-05-09T18:57:24+08:00",
          "utc": "1981-05-09T10:57:24Z",
          "ms": 358253844310.2676
        },
        "end": {
          "local": "1981-05-10T18:21:56+08:00",
          "utc": "1981-05-10T10:21:56Z",
          "ms": 358338115869.4165
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-09T18:57:24+08:00",
          "utc": "1981-05-09T10:57:24Z",
          "ms": 358253844310.2676
        },
        "end": {
          "local": "1981-05-10T18:21:56+08:00",
          "utc": "1981-05-10T10:21:56Z",
          "ms": 358338115869.4165
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-05-09",
          "window": {
            "start": {
              "local": "1981-05-09T11:06:13+08:00",
              "utc": "1981-05-09T03:06:13Z",
              "ms": 358225572611.73486
            },
            "end": {
              "local": "1981-05-09T11:54:13+08:00",
              "utc": "1981-05-09T03:54:13Z",
              "ms": 358228452611.73486
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-05-10",
          "window": {
            "start": {
              "local": "1981-05-10T11:06:10+08:00",
              "utc": "1981-05-10T03:06:10Z",
              "ms": 358311969696.4889
            },
            "end": {
              "local": "1981-05-10T11:54:10+08:00",
              "utc": "1981-05-10T03:54:10Z",
              "ms": 358314849696.4889
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Saptamī runs from 18:57 on Sat 9 May to 18:22 on Sun 10 May.",
          "fact": "1981-05-09T10:57:24Z → 1981-05-10T10:21:56Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:06–11:54 on the 9th, 11:06–11:54 on the 10th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Saptamī must be present during madhyāhna. It covers 0 of 48 minutes on the 9th and 48 of 48 on the 10th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 23266 s"
        },
        {
          "step": "ruling",
          "text": "Gaṅgotpatti, Harbin, 1981: Sunday 10 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "gangotpatti",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 7 Gangotpatti, (madhyahna vyapini, if occurs on two successive days, the first day is to be observed), Jahnu saptami, Sarkara saptami."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-10",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-10",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Gaṅgotpatti (Ganga Saptami) 1981 falls on Sunday 10 May. Saptamī runs from 18:57 on Sat 9 May to 18:22 on Sun 10 May and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/gangotpatti",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-05-14",
      "festival": "ekadashi",
      "name": "Mohinī Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-14",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 19008,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-05-13T20:52:56+08:00",
          "utc": "1981-05-13T12:52:56Z",
          "ms": 358606375683.9335
        },
        "end": {
          "local": "1981-05-14T22:46:14+08:00",
          "utc": "1981-05-14T14:46:14Z",
          "ms": 358699573655.84125
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-13T20:52:56+08:00",
          "utc": "1981-05-13T12:52:56Z",
          "ms": 358606375683.9335
        },
        "end": {
          "local": "1981-05-14T22:46:14+08:00",
          "utc": "1981-05-14T14:46:14Z",
          "ms": 358699573655.84125
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-05-14",
          "window": {
            "start": {
              "local": "1981-05-14T04:04:14+08:00",
              "utc": "1981-05-13T20:04:14Z",
              "ms": 358632253643.5425
            },
            "end": {
              "local": "1981-05-14T04:04:14+08:00",
              "utc": "1981-05-13T20:04:14Z",
              "ms": 358632253643.5425
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-05-15",
          "window": {
            "start": {
              "local": "1981-05-15T04:03:02+08:00",
              "utc": "1981-05-14T20:03:02Z",
              "ms": 358718582075.4461
            },
            "end": {
              "local": "1981-05-15T04:03:02+08:00",
              "utc": "1981-05-14T20:03:02Z",
              "ms": 358718582075.4461
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 20:53 on Wed 13 May to 22:46 on Thu 14 May.",
          "fact": "1981-05-13T12:52:56Z → 1981-05-14T14:46:14Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 04:04 on the 14th and 04:03 on the 15th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 14th and is not on the 15th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 19008 s"
        },
        {
          "step": "ruling",
          "text": "Mohinī Ekādaśī, Harbin, 1981: Thursday 14 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-14",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-14",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Mohinī Ekādaśī 1981 falls on Thursday 14 May. Ekādaśī runs from 20:53 on Wed 13 May to 22:46 on Thu 14 May and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-05-14",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/parashurama-dvadashi",
      "festival": "parashurama-dvadashi",
      "name": "Paraśurāma Dvādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-15",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 36550,
      "anga": {
        "type": "tithi",
        "index": 11,
        "key": "dvadashi",
        "name": "Dvādaśī",
        "start": {
          "local": "1981-05-14T22:46:14+08:00",
          "utc": "1981-05-14T14:46:14Z",
          "ms": 358699573655.84125
        },
        "end": {
          "local": "1981-05-16T00:56:54+08:00",
          "utc": "1981-05-15T16:56:54Z",
          "ms": 358793813614.6534
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-14T22:46:14+08:00",
          "utc": "1981-05-14T14:46:14Z",
          "ms": 358699573655.84125
        },
        "end": {
          "local": "1981-05-16T00:56:54+08:00",
          "utc": "1981-05-15T16:56:54Z",
          "ms": 358793813614.6534
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-05-15",
          "window": {
            "start": {
              "local": "1981-05-15T11:06:03+08:00",
              "utc": "1981-05-15T03:06:03Z",
              "ms": 358743963218.10486
            },
            "end": {
              "local": "1981-05-15T11:54:03+08:00",
              "utc": "1981-05-15T03:54:03Z",
              "ms": 358746843218.10486
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-05-16",
          "window": {
            "start": {
              "local": "1981-05-16T11:06:04+08:00",
              "utc": "1981-05-16T03:06:04Z",
              "ms": 358830363545.4562
            },
            "end": {
              "local": "1981-05-16T11:54:04+08:00",
              "utc": "1981-05-16T03:54:04Z",
              "ms": 358833243545.4562
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvādaśī runs from 22:46 on Thu 14 May to 00:57 on Sat 16 May.",
          "fact": "1981-05-14T14:46:14Z → 1981-05-15T16:56:54Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:06–11:54 on the 15th, 11:06–11:54 on the 16th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvādaśī must be present during madhyāhna. It covers 48 of 48 minutes on the 15th and 0 of 48 on the 16th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 36550 s"
        },
        {
          "step": "ruling",
          "text": "Paraśurāma Dvādaśī, Harbin, 1981: Friday 15 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "parashurama-dvadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 12 Parasurama dvadasi (purvaviddha), Rukmini dvadasi (purvaviddha)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-15",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-15",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Paraśurāma Dvādaśī 1981 falls on Friday 15 May. Dvādaśī runs from 22:46 on Thu 14 May to 00:57 on Sat 16 May and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/parashurama-dvadashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/rukmini-dvadashi",
      "festival": "rukmini-dvadashi",
      "name": "Rukmiṇī Dvādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-15",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 36550,
      "anga": {
        "type": "tithi",
        "index": 11,
        "key": "dvadashi",
        "name": "Dvādaśī",
        "start": {
          "local": "1981-05-14T22:46:14+08:00",
          "utc": "1981-05-14T14:46:14Z",
          "ms": 358699573655.84125
        },
        "end": {
          "local": "1981-05-16T00:56:54+08:00",
          "utc": "1981-05-15T16:56:54Z",
          "ms": 358793813614.6534
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-14T22:46:14+08:00",
          "utc": "1981-05-14T14:46:14Z",
          "ms": 358699573655.84125
        },
        "end": {
          "local": "1981-05-16T00:56:54+08:00",
          "utc": "1981-05-15T16:56:54Z",
          "ms": 358793813614.6534
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-05-15",
          "window": {
            "start": {
              "local": "1981-05-15T11:06:03+08:00",
              "utc": "1981-05-15T03:06:03Z",
              "ms": 358743963218.10486
            },
            "end": {
              "local": "1981-05-15T11:54:03+08:00",
              "utc": "1981-05-15T03:54:03Z",
              "ms": 358746843218.10486
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-05-16",
          "window": {
            "start": {
              "local": "1981-05-16T11:06:04+08:00",
              "utc": "1981-05-16T03:06:04Z",
              "ms": 358830363545.4562
            },
            "end": {
              "local": "1981-05-16T11:54:04+08:00",
              "utc": "1981-05-16T03:54:04Z",
              "ms": 358833243545.4562
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvādaśī runs from 22:46 on Thu 14 May to 00:57 on Sat 16 May.",
          "fact": "1981-05-14T14:46:14Z → 1981-05-15T16:56:54Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:06–11:54 on the 15th, 11:06–11:54 on the 16th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvādaśī must be present during madhyāhna. It covers 48 of 48 minutes on the 15th and 0 of 48 on the 16th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 36550 s"
        },
        {
          "step": "ruling",
          "text": "Rukmiṇī Dvādaśī, Harbin, 1981: Friday 15 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "rukmini-dvadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 12 Parasurama dvadasi (purvaviddha), Rukmini dvadasi (purvaviddha)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-15",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-15",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Rukmiṇī Dvādaśī 1981 falls on Friday 15 May. Dvādaśī runs from 22:46 on Thu 14 May to 00:57 on Sat 16 May and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/rukmini-dvadashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-05-16",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 17231,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-05-16T00:56:54+08:00",
          "utc": "1981-05-15T16:56:54Z",
          "ms": 358793813614.6534
        },
        "end": {
          "local": "1981-05-17T03:17:16+08:00",
          "utc": "1981-05-16T19:17:16Z",
          "ms": 358888636380.0035
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-16T00:56:54+08:00",
          "utc": "1981-05-15T16:56:54Z",
          "ms": 358793813614.6534
        },
        "end": {
          "local": "1981-05-17T03:17:16+08:00",
          "utc": "1981-05-16T19:17:16Z",
          "ms": 358888636380.0035
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-05-15",
          "window": {
            "start": {
              "local": "1981-05-15T18:57:04+08:00",
              "utc": "1981-05-15T10:57:04Z",
              "ms": 358772224360.7636
            },
            "end": {
              "local": "1981-05-15T20:09:43+08:00",
              "utc": "1981-05-15T12:09:43Z",
              "ms": 358776582750.3482
            }
          },
          "covered_min": 0,
          "window_min": 73,
          "qualifies": false
        },
        {
          "local_date": "1981-05-16",
          "window": {
            "start": {
              "local": "1981-05-16T18:58:15+08:00",
              "utc": "1981-05-16T10:58:15Z",
              "ms": 358858694808.2643
            },
            "end": {
              "local": "1981-05-16T20:10:35+08:00",
              "utc": "1981-05-16T12:10:35Z",
              "ms": 358863034740.83685
            }
          },
          "covered_min": 72,
          "window_min": 72,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 00:57 on Sat 16 May to 03:17 on Sun 17 May.",
          "fact": "1981-05-15T16:56:54Z → 1981-05-16T19:17:16Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:57–20:10 on the 15th, 18:58–20:11 on the 16th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 73 minutes on the 15th and 72 of 72 on the 16th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 17231 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Saturday 16 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Saturday 16 May. Trayodaśī runs from 00:57 on Sat 16 May to 03:17 on Sun 17 May and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-05-16",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/nrisimha-chaturdashi",
      "festival": "nrisimha-chaturdashi",
      "name": "Nṛsiṃha Caturdaśī",
      "everyday": "Narasimha Jayanti",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-17",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 25602,
      "anga": {
        "type": "tithi",
        "index": 13,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-05-17T03:17:16+08:00",
          "utc": "1981-05-16T19:17:16Z",
          "ms": 358888636380.0035
        },
        "end": {
          "local": "1981-05-18T05:41:09+08:00",
          "utc": "1981-05-17T21:41:09Z",
          "ms": 358983668667.4497
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-17T03:17:16+08:00",
          "utc": "1981-05-16T19:17:16Z",
          "ms": 358888636380.0035
        },
        "end": {
          "local": "1981-05-18T05:41:09+08:00",
          "utc": "1981-05-17T21:41:09Z",
          "ms": 358983668667.4497
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-05-16",
          "window": {
            "start": {
              "local": "1981-05-16T18:58:15+08:00",
              "utc": "1981-05-16T10:58:15Z",
              "ms": 358858694808.2643
            },
            "end": {
              "local": "1981-05-16T20:10:35+08:00",
              "utc": "1981-05-16T12:10:35Z",
              "ms": 358863034740.83685
            }
          },
          "covered_min": 0,
          "window_min": 72,
          "qualifies": false
        },
        {
          "local_date": "1981-05-17",
          "window": {
            "start": {
              "local": "1981-05-17T18:59:25+08:00",
              "utc": "1981-05-17T10:59:25Z",
              "ms": 358945164523.79266
            },
            "end": {
              "local": "1981-05-17T20:11:26+08:00",
              "utc": "1981-05-17T12:11:26Z",
              "ms": 358949486343.58777
            }
          },
          "covered_min": 72,
          "window_min": 72,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 03:17 on Sun 17 May to 05:41 on Mon 18 May.",
          "fact": "1981-05-16T19:17:16Z → 1981-05-17T21:41:09Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:58–20:11 on the 16th, 18:59–20:11 on the 17th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during pradoṣa. It covers 0 of 72 minutes on the 16th and 72 of 72 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 25602 s"
        },
        {
          "step": "ruling",
          "text": "Nṛsiṃha Caturdaśī, Harbin, 1981: Sunday 17 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "nrisimha-chaturdashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 14 Nrsimha caturdasi (pradosa vyapini — if it occurs on two successive days, the second day is to be observed, special when combined with naksatra 'Svati', yoga 'Siddhi' and 'Saturday')."
          }
        ],
        "not_evaluated": "The row calls the day special with Svātī nakṣatra, Siddhi yoga and a Saturday; none is tested.",
        "kaala": "pradosha",
        "priority": "paraviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-17",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-17",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Nṛsiṃha Caturdaśī (Narasimha Jayanti) 1981 falls on Sunday 17 May. Caturdaśī runs from 03:17 on Sun 17 May to 05:41 on Mon 18 May and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/nrisimha-chaturdashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/buddha-purnima",
      "festival": "buddha-purnima",
      "name": "Buddha Pūrṇimā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-18",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 10953,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-05-18T05:41:09+08:00",
          "utc": "1981-05-17T21:41:09Z",
          "ms": 358983668667.4497
        },
        "end": {
          "local": "1981-05-19T08:03:35+08:00",
          "utc": "1981-05-19T00:03:35Z",
          "ms": 359078614902.99506
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-18T05:41:09+08:00",
          "utc": "1981-05-17T21:41:09Z",
          "ms": 358983668667.4497
        },
        "end": {
          "local": "1981-05-19T08:03:35+08:00",
          "utc": "1981-05-19T00:03:35Z",
          "ms": 359078614902.99506
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-05-18",
          "window": {
            "start": {
              "local": "1981-05-18T11:06:06+08:00",
              "utc": "1981-05-18T03:06:06Z",
              "ms": 359003165819.90137
            },
            "end": {
              "local": "1981-05-18T11:54:06+08:00",
              "utc": "1981-05-18T03:54:06Z",
              "ms": 359006045819.90137
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-05-19",
          "window": {
            "start": {
              "local": "1981-05-19T11:06:08+08:00",
              "utc": "1981-05-19T03:06:08Z",
              "ms": 359089567763.6211
            },
            "end": {
              "local": "1981-05-19T11:54:08+08:00",
              "utc": "1981-05-19T03:54:08Z",
              "ms": 359092447763.6211
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 05:41 on Mon 18 May to 08:04 on Tue 19 May.",
          "fact": "1981-05-17T21:41:09Z → 1981-05-19T00:03:35Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:06–11:54 on the 18th, 11:06–11:54 on the 19th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during madhyāhna. It covers 48 of 48 minutes on the 18th and 0 of 48 on the 19th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 10953 s"
        },
        {
          "step": "ruling",
          "text": "Buddha Pūrṇimā, Harbin, 1981: Monday 18 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "buddha-purnima",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Sampat gauri vrata (paraviddha), Phuladola (Bengal & Orissa) (paraviddha), Gandhesvari puja (Bengal) (purvaviddha), Buddha purnima, Vaisakhi purnima."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-18",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-18",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Buddha Pūrṇimā 1981 falls on Monday 18 May. Pūrṇimā runs from 05:41 on Mon 18 May to 08:04 on Tue 19 May and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/buddha-purnima",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sampat-gauri-vrata",
      "festival": "sampat-gauri-vrata",
      "name": "Sampat Gaurī Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-18",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 10953,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-05-18T05:41:09+08:00",
          "utc": "1981-05-17T21:41:09Z",
          "ms": 358983668667.4497
        },
        "end": {
          "local": "1981-05-19T08:03:35+08:00",
          "utc": "1981-05-19T00:03:35Z",
          "ms": 359078614902.99506
        },
        "month": {
          "amanta": 1,
          "purnimanta": 1,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Vaiśākha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-18T05:41:09+08:00",
          "utc": "1981-05-17T21:41:09Z",
          "ms": 358983668667.4497
        },
        "end": {
          "local": "1981-05-19T08:03:35+08:00",
          "utc": "1981-05-19T00:03:35Z",
          "ms": 359078614902.99506
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-05-18",
          "window": {
            "start": {
              "local": "1981-05-18T11:06:06+08:00",
              "utc": "1981-05-18T03:06:06Z",
              "ms": 359003165819.90137
            },
            "end": {
              "local": "1981-05-18T11:54:06+08:00",
              "utc": "1981-05-18T03:54:06Z",
              "ms": 359006045819.90137
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-05-19",
          "window": {
            "start": {
              "local": "1981-05-19T11:06:08+08:00",
              "utc": "1981-05-19T03:06:08Z",
              "ms": 359089567763.6211
            },
            "end": {
              "local": "1981-05-19T11:54:08+08:00",
              "utc": "1981-05-19T03:54:08Z",
              "ms": 359092447763.6211
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 05:41 on Mon 18 May to 08:04 on Tue 19 May.",
          "fact": "1981-05-17T21:41:09Z → 1981-05-19T00:03:35Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:06–11:54 on the 18th, 11:06–11:54 on the 19th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during madhyāhna. It covers 48 of 48 minutes on the 18th and 0 of 48 on the 19th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 10953 s"
        },
        {
          "step": "ruling",
          "text": "Sampat Gaurī Vrata, Harbin, 1981: Monday 18 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sampat-gauri-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Sampat gauri vrata (paraviddha), Phuladola (Bengal & Orissa) (paraviddha), Gandhesvari puja (Bengal) (purvaviddha), Buddha purnima, Vaisakhi purnima."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-18",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-18",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Sampat Gaurī Vrata 1981 falls on Monday 18 May. Pūrṇimā runs from 05:41 on Mon 18 May to 08:04 on Tue 19 May and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sampat-gauri-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-05-22",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-22",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 24724,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-05-22T14:19:33+08:00",
          "utc": "1981-05-22T06:19:33Z",
          "ms": 359360373240.8377
        },
        "end": {
          "local": "1981-05-23T15:51:16+08:00",
          "utc": "1981-05-23T07:51:16Z",
          "ms": 359452276358.73816
        },
        "month": {
          "amanta": 1,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-22T14:19:33+08:00",
          "utc": "1981-05-22T06:19:33Z",
          "ms": 359360373240.8377
        },
        "end": {
          "local": "1981-05-23T15:51:16+08:00",
          "utc": "1981-05-23T07:51:16Z",
          "ms": 359452276358.73816
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-05-22",
          "window": {
            "start": {
              "local": "1981-05-22T21:55:35+08:00",
              "utc": "1981-05-22T13:55:35Z",
              "ms": 359387735259.9373
            },
            "end": {
              "local": "1981-05-22T21:55:35+08:00",
              "utc": "1981-05-22T13:55:35Z",
              "ms": 359387735259.9373
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-05-23",
          "window": {
            "start": {
              "local": "1981-05-23T22:43:21+08:00",
              "utc": "1981-05-23T14:43:21Z",
              "ms": 359477000603.32965
            },
            "end": {
              "local": "1981-05-23T22:43:21+08:00",
              "utc": "1981-05-23T14:43:21Z",
              "ms": 359477000603.32965
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 14:20 on Fri 22 May to 15:51 on Sat 23 May.",
          "fact": "1981-05-22T06:19:33Z → 1981-05-23T07:51:16Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 21:56 on the 22nd and 22:43 on the 23rd.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is on the 22nd and is not on the 23rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 24724 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Friday 22 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-22",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-22",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Friday 22 May. Caturthī runs from 14:20 on Fri 22 May to 15:51 on Sat 23 May and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-05-22",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-05-30",
      "festival": "ekadashi",
      "name": "Aparā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-30",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 21945,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-05-29T12:43:42+08:00",
          "utc": "1981-05-29T04:43:42Z",
          "ms": 359959422412.1719
        },
        "end": {
          "local": "1981-05-30T09:54:46+08:00",
          "utc": "1981-05-30T01:54:46Z",
          "ms": 360035686264.41327
        },
        "month": {
          "amanta": 1,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-29T12:43:42+08:00",
          "utc": "1981-05-29T04:43:42Z",
          "ms": 359959422412.1719
        },
        "end": {
          "local": "1981-05-30T09:54:46+08:00",
          "utc": "1981-05-30T01:54:46Z",
          "ms": 360035686264.41327
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-05-29",
          "window": {
            "start": {
              "local": "1981-05-29T03:49:43+08:00",
              "utc": "1981-05-28T19:49:43Z",
              "ms": 359927382901.19666
            },
            "end": {
              "local": "1981-05-29T03:49:43+08:00",
              "utc": "1981-05-28T19:49:43Z",
              "ms": 359927382901.19666
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-05-30",
          "window": {
            "start": {
              "local": "1981-05-30T03:49:02+08:00",
              "utc": "1981-05-29T19:49:02Z",
              "ms": 360013741639.3577
            },
            "end": {
              "local": "1981-05-30T03:49:02+08:00",
              "utc": "1981-05-29T19:49:02Z",
              "ms": 360013741639.3577
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 12:44 on Fri 29 May to 09:55 on Sat 30 May.",
          "fact": "1981-05-29T04:43:42Z → 1981-05-30T01:54:46Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 03:50 on the 29th and 03:49 on the 30th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 29th and is on the 30th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 21945 s"
        },
        {
          "step": "ruling",
          "text": "Aparā Ekādaśī, Harbin, 1981: Saturday 30 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-30",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-30",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Aparā Ekādaśī 1981 falls on Saturday 30 May. Ekādaśī runs from 12:44 on Fri 29 May to 09:55 on Sat 30 May and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-05-30",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-05-31",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-05-31",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 23924,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-05-31T06:37:36+08:00",
          "utc": "1981-05-30T22:37:36Z",
          "ms": 360110256475.55414
        },
        "end": {
          "local": "1981-06-01T03:01:13+08:00",
          "utc": "1981-05-31T19:01:13Z",
          "ms": 360183673205.97363
        },
        "month": {
          "amanta": 1,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-05-31T06:37:36+08:00",
          "utc": "1981-05-30T22:37:36Z",
          "ms": 360110256475.55414
        },
        "end": {
          "local": "1981-06-01T03:01:13+08:00",
          "utc": "1981-05-31T19:01:13Z",
          "ms": 360183673205.97363
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-05-30",
          "window": {
            "start": {
              "local": "1981-05-30T19:13:05+08:00",
              "utc": "1981-05-30T11:13:05Z",
              "ms": 360069184674.5902
            },
            "end": {
              "local": "1981-05-30T20:21:47+08:00",
              "utc": "1981-05-30T12:21:47Z",
              "ms": 360073307069.6946
            }
          },
          "covered_min": 0,
          "window_min": 69,
          "qualifies": false
        },
        {
          "local_date": "1981-05-31",
          "window": {
            "start": {
              "local": "1981-05-31T19:13:59+08:00",
              "utc": "1981-05-31T11:13:59Z",
              "ms": 360155639470.0886
            },
            "end": {
              "local": "1981-05-31T20:22:30+08:00",
              "utc": "1981-05-31T12:22:30Z",
              "ms": 360159749662.8453
            }
          },
          "covered_min": 69,
          "window_min": 69,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 06:38 on Sun 31 May to 03:01 on Mon 1 Jun.",
          "fact": "1981-05-30T22:37:36Z → 1981-05-31T19:01:13Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 19:13–20:22 on the 30th, 19:14–20:22 on the 31st.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 69 minutes on the 30th and 69 of 69 on the 31st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 23924 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Sunday 31 May.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-05-31",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-05-31",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Sunday 31 May. Trayodaśī runs from 06:38 on Sun 31 May to 03:01 on Mon 1 Jun and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-05-31",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-06-01",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-01",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 520,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-06-01T03:01:13+08:00",
          "utc": "1981-05-31T19:01:13Z",
          "ms": 360183673205.97363
        },
        "end": {
          "local": "1981-06-01T23:15:42+08:00",
          "utc": "1981-06-01T15:15:42Z",
          "ms": 360256541959.85
        },
        "month": {
          "amanta": 1,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Vaiśākha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-01T03:01:13+08:00",
          "utc": "1981-05-31T19:01:13Z",
          "ms": 360183673205.97363
        },
        "end": {
          "local": "1981-06-01T23:15:42+08:00",
          "utc": "1981-06-01T15:15:42Z",
          "ms": 360256541959.85
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-05-31",
          "window": {
            "start": {
              "local": "1981-05-31T23:06:53+08:00",
              "utc": "1981-05-31T15:06:53Z",
              "ms": 360169612692.92615
            },
            "end": {
              "local": "1981-05-31T23:54:53+08:00",
              "utc": "1981-05-31T15:54:53Z",
              "ms": 360172492692.92615
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-06-01",
          "window": {
            "start": {
              "local": "1981-06-01T23:07:02+08:00",
              "utc": "1981-06-01T15:07:02Z",
              "ms": 360256022153.07434
            },
            "end": {
              "local": "1981-06-01T23:55:02+08:00",
              "utc": "1981-06-01T15:55:02Z",
              "ms": 360258902153.07434
            }
          },
          "covered_min": 9,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 03:01 on Mon 1 Jun to 23:16 on Mon 1 Jun.",
          "fact": "1981-05-31T19:01:13Z → 1981-06-01T15:15:42Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:07–23:55 on the 31st, 23:07–23:55 on the 1st.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 0 of 48 minutes on the 31st and 9 of 48 on the 1st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 520 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Monday 1 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-01",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-01",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Monday 1 June. Caturdaśī runs from 03:01 on Mon 1 Jun to 23:16 on Mon 1 Jun and covers 9 of 48 minutes of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-06-01",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/rambha-tritiya",
      "festival": "rambha-tritiya",
      "name": "Rambhā Tṛtīyā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-05",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 3248,
      "anga": {
        "type": "tithi",
        "index": 2,
        "key": "tritiya",
        "name": "Tṛtīyā",
        "start": {
          "local": "1981-06-04T12:50:52+08:00",
          "utc": "1981-06-04T04:50:52Z",
          "ms": 360478251773.92346
        },
        "end": {
          "local": "1981-06-05T10:13:48+08:00",
          "utc": "1981-06-05T02:13:48Z",
          "ms": 360555228294.4469
        },
        "month": {
          "amanta": 2,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-04T12:50:52+08:00",
          "utc": "1981-06-04T04:50:52Z",
          "ms": 360478251773.92346
        },
        "end": {
          "local": "1981-06-05T10:13:48+08:00",
          "utc": "1981-06-05T02:13:48Z",
          "ms": 360555228294.4469
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-06-04",
          "window": {
            "start": {
              "local": "1981-06-04T11:07:47+08:00",
              "utc": "1981-06-04T03:07:47Z",
              "ms": 360472066583.1453
            },
            "end": {
              "local": "1981-06-04T11:55:47+08:00",
              "utc": "1981-06-04T03:55:47Z",
              "ms": 360474946583.1453
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-06-05",
          "window": {
            "start": {
              "local": "1981-06-05T11:07:56+08:00",
              "utc": "1981-06-05T03:07:56Z",
              "ms": 360558476338.9624
            },
            "end": {
              "local": "1981-06-05T11:55:56+08:00",
              "utc": "1981-06-05T03:55:56Z",
              "ms": 360561356338.9624
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "second-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Tṛtīyā runs from 12:51 on Thu 4 Jun to 10:14 on Fri 5 Jun.",
          "fact": "1981-06-04T04:50:52Z → 1981-06-05T02:13:48Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:08–11:56 on the 4th, 11:08–11:56 on the 5th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Tṛtīyā must be present during madhyāhna. It covers 0 of 48 minutes on the 4th and 0 of 48 on the 5th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Neither midday qualifies. The rule takes the second day.",
          "fact": "priority: purvaviddha → second-day · margin 3248 s"
        },
        {
          "step": "ruling",
          "text": "Rambhā Tṛtīyā, Harbin, 1981: Friday 5 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "rambha-tritiya",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 3 Rambha trtiya (purvaviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-05",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-04",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Rambhā Tṛtīyā 1981 falls on Friday 5 June. Tṛtīyā runs from 12:51 on Thu 4 Jun to 10:14 on Fri 5 Jun, and reaches madhyāhna on neither day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/rambha-tritiya",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-06-05",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-05",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 3248,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-06-05T10:13:48+08:00",
          "utc": "1981-06-05T02:13:48Z",
          "ms": 360555228294.4469
        },
        "end": {
          "local": "1981-06-06T08:16:40+08:00",
          "utc": "1981-06-06T00:16:40Z",
          "ms": 360634600046.394
        },
        "month": {
          "amanta": 2,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-05T10:13:48+08:00",
          "utc": "1981-06-05T02:13:48Z",
          "ms": 360555228294.4469
        },
        "end": {
          "local": "1981-06-06T08:16:40+08:00",
          "utc": "1981-06-06T00:16:40Z",
          "ms": 360634600046.394
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-06-05",
          "window": {
            "start": {
              "local": "1981-06-05T11:07:56+08:00",
              "utc": "1981-06-05T03:07:56Z",
              "ms": 360558476338.9624
            },
            "end": {
              "local": "1981-06-05T11:55:56+08:00",
              "utc": "1981-06-05T03:55:56Z",
              "ms": 360561356338.9624
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-06-06",
          "window": {
            "start": {
              "local": "1981-06-06T11:08:06+08:00",
              "utc": "1981-06-06T03:08:06Z",
              "ms": 360644886398.6016
            },
            "end": {
              "local": "1981-06-06T11:56:06+08:00",
              "utc": "1981-06-06T03:56:06Z",
              "ms": 360647766398.6016
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 10:14 on Fri 5 Jun to 08:17 on Sat 6 Jun.",
          "fact": "1981-06-05T02:13:48Z → 1981-06-06T00:16:40Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:08–11:56 on the 5th, 11:08–11:56 on the 6th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 48 of 48 minutes on the 5th and 0 of 48 on the 6th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 3248 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Friday 5 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-05",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-05",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Friday 5 June. Caturthī runs from 10:14 on Fri 5 Jun to 08:17 on Sat 6 Jun and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-06-05",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/aranya-gauri-vrata",
      "festival": "aranya-gauri-vrata",
      "name": "Araṇya Gaurī Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-07",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 14594,
      "anga": {
        "type": "tithi",
        "index": 5,
        "key": "shashthi",
        "name": "Ṣaṣṭhī",
        "start": {
          "local": "1981-06-07T07:05:02+08:00",
          "utc": "1981-06-06T23:05:02Z",
          "ms": 360716702311.4888
        },
        "end": {
          "local": "1981-06-08T06:41:30+08:00",
          "utc": "1981-06-07T22:41:30Z",
          "ms": 360801690136.3714
        },
        "month": {
          "amanta": 2,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-07T07:05:02+08:00",
          "utc": "1981-06-06T23:05:02Z",
          "ms": 360716702311.4888
        },
        "end": {
          "local": "1981-06-08T06:41:30+08:00",
          "utc": "1981-06-07T22:41:30Z",
          "ms": 360801690136.3714
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-06-07",
          "window": {
            "start": {
              "local": "1981-06-07T11:08:17+08:00",
              "utc": "1981-06-07T03:08:17Z",
              "ms": 360731296740.33875
            },
            "end": {
              "local": "1981-06-07T11:56:17+08:00",
              "utc": "1981-06-07T03:56:17Z",
              "ms": 360734176740.33875
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-06-08",
          "window": {
            "start": {
              "local": "1981-06-08T11:08:27+08:00",
              "utc": "1981-06-08T03:08:27Z",
              "ms": 360817707343.2737
            },
            "end": {
              "local": "1981-06-08T11:56:27+08:00",
              "utc": "1981-06-08T03:56:27Z",
              "ms": 360820587343.2737
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ṣaṣṭhī runs from 07:05 on Sun 7 Jun to 06:42 on Mon 8 Jun.",
          "fact": "1981-06-06T23:05:02Z → 1981-06-07T22:41:30Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:08–11:56 on the 7th, 11:08–11:56 on the 8th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ṣaṣṭhī must be present during madhyāhna. It covers 48 of 48 minutes on the 7th and 0 of 48 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 14594 s"
        },
        {
          "step": "ruling",
          "text": "Araṇya Gaurī Vrata, Harbin, 1981: Sunday 7 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "aranya-gauri-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 6 Aranya sasthi, Aranya gauri vrata, (paraviddha), Skanda sasthi, (purvaviddha), Sitala sasthi yatra (Orissa)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-07",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-07",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Araṇya Gaurī Vrata 1981 falls on Sunday 7 June. Ṣaṣṭhī runs from 07:05 on Sun 7 Jun to 06:42 on Mon 8 Jun and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/aranya-gauri-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/skanda-shashthi-jyaishtha",
      "festival": "skanda-shashthi-jyaishtha",
      "name": "Skanda Ṣaṣṭhī (Jyaiṣṭha)",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-07",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 14594,
      "anga": {
        "type": "tithi",
        "index": 5,
        "key": "shashthi",
        "name": "Ṣaṣṭhī",
        "start": {
          "local": "1981-06-07T07:05:02+08:00",
          "utc": "1981-06-06T23:05:02Z",
          "ms": 360716702311.4888
        },
        "end": {
          "local": "1981-06-08T06:41:30+08:00",
          "utc": "1981-06-07T22:41:30Z",
          "ms": 360801690136.3714
        },
        "month": {
          "amanta": 2,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-07T07:05:02+08:00",
          "utc": "1981-06-06T23:05:02Z",
          "ms": 360716702311.4888
        },
        "end": {
          "local": "1981-06-08T06:41:30+08:00",
          "utc": "1981-06-07T22:41:30Z",
          "ms": 360801690136.3714
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-06-07",
          "window": {
            "start": {
              "local": "1981-06-07T11:08:17+08:00",
              "utc": "1981-06-07T03:08:17Z",
              "ms": 360731296740.33875
            },
            "end": {
              "local": "1981-06-07T11:56:17+08:00",
              "utc": "1981-06-07T03:56:17Z",
              "ms": 360734176740.33875
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-06-08",
          "window": {
            "start": {
              "local": "1981-06-08T11:08:27+08:00",
              "utc": "1981-06-08T03:08:27Z",
              "ms": 360817707343.2737
            },
            "end": {
              "local": "1981-06-08T11:56:27+08:00",
              "utc": "1981-06-08T03:56:27Z",
              "ms": 360820587343.2737
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ṣaṣṭhī runs from 07:05 on Sun 7 Jun to 06:42 on Mon 8 Jun.",
          "fact": "1981-06-06T23:05:02Z → 1981-06-07T22:41:30Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:08–11:56 on the 7th, 11:08–11:56 on the 8th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ṣaṣṭhī must be present during madhyāhna. It covers 48 of 48 minutes on the 7th and 0 of 48 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 14594 s"
        },
        {
          "step": "ruling",
          "text": "Skanda Ṣaṣṭhī (Jyaiṣṭha), Harbin, 1981: Sunday 7 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "skanda-shashthi-jyaishtha",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 6 Aranya sasthi, Aranya gauri vrata, (paraviddha), Skanda sasthi, (purvaviddha), Sitala sasthi yatra (Orissa)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-07",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-07",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Skanda Ṣaṣṭhī (Jyaiṣṭha) 1981 falls on Sunday 7 June. Ṣaṣṭhī runs from 07:05 on Sun 7 Jun to 06:42 on Mon 8 Jun and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/skanda-shashthi-jyaishtha",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-06-13",
      "festival": "ekadashi",
      "name": "Nirjalā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-13",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 29637,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-06-12T11:57:32+08:00",
          "utc": "1981-06-12T03:57:32Z",
          "ms": 361166252488.30054
        },
        "end": {
          "local": "1981-06-13T14:17:15+08:00",
          "utc": "1981-06-13T06:17:15Z",
          "ms": 361261034614.17194
        },
        "month": {
          "amanta": 2,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-12T11:57:32+08:00",
          "utc": "1981-06-12T03:57:32Z",
          "ms": 361166252488.30054
        },
        "end": {
          "local": "1981-06-13T14:17:15+08:00",
          "utc": "1981-06-13T06:17:15Z",
          "ms": 361261034614.17194
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-06-12",
          "window": {
            "start": {
              "local": "1981-06-12T03:43:36+08:00",
              "utc": "1981-06-11T19:43:36Z",
              "ms": 361136615953.15625
            },
            "end": {
              "local": "1981-06-12T03:43:36+08:00",
              "utc": "1981-06-11T19:43:36Z",
              "ms": 361136615953.15625
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-06-13",
          "window": {
            "start": {
              "local": "1981-06-13T03:43:27+08:00",
              "utc": "1981-06-12T19:43:27Z",
              "ms": 361223007439.0557
            },
            "end": {
              "local": "1981-06-13T03:43:27+08:00",
              "utc": "1981-06-12T19:43:27Z",
              "ms": 361223007439.0557
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 11:58 on Fri 12 Jun to 14:17 on Sat 13 Jun.",
          "fact": "1981-06-12T03:57:32Z → 1981-06-13T06:17:15Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 03:44 on the 12th and 03:43 on the 13th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 12th and is on the 13th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 29637 s"
        },
        {
          "step": "ruling",
          "text": "Nirjalā Ekādaśī, Harbin, 1981: Saturday 13 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-13",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-13",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Nirjalā Ekādaśī 1981 falls on Saturday 13 June. Ekādaśī runs from 11:58 on Fri 12 Jun to 14:17 on Sat 13 Jun and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-06-13",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shri-rama-dvadashi",
      "festival": "shri-rama-dvadashi",
      "name": "Śrī Rāma Dvādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-14",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 8391,
      "anga": {
        "type": "tithi",
        "index": 11,
        "key": "dvadashi",
        "name": "Dvādaśī",
        "start": {
          "local": "1981-06-13T14:17:15+08:00",
          "utc": "1981-06-13T06:17:15Z",
          "ms": 361261034614.17194
        },
        "end": {
          "local": "1981-06-14T16:41:10+08:00",
          "utc": "1981-06-14T08:41:10Z",
          "ms": 361356069912.9576
        },
        "month": {
          "amanta": 2,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-13T14:17:15+08:00",
          "utc": "1981-06-13T06:17:15Z",
          "ms": 361261034614.17194
        },
        "end": {
          "local": "1981-06-14T16:41:10+08:00",
          "utc": "1981-06-14T08:41:10Z",
          "ms": 361356069912.9576
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-06-13",
          "window": {
            "start": {
              "local": "1981-06-13T11:09:24+08:00",
              "utc": "1981-06-13T03:09:24Z",
              "ms": 361249763578.5582
            },
            "end": {
              "local": "1981-06-13T11:57:24+08:00",
              "utc": "1981-06-13T03:57:24Z",
              "ms": 361252643578.5582
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-06-14",
          "window": {
            "start": {
              "local": "1981-06-14T11:09:35+08:00",
              "utc": "1981-06-14T03:09:35Z",
              "ms": 361336175333.4041
            },
            "end": {
              "local": "1981-06-14T11:57:35+08:00",
              "utc": "1981-06-14T03:57:35Z",
              "ms": 361339055333.4041
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvādaśī runs from 14:17 on Sat 13 Jun to 16:41 on Sun 14 Jun.",
          "fact": "1981-06-13T06:17:15Z → 1981-06-14T08:41:10Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:09–11:57 on the 13th, 11:10–11:58 on the 14th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvādaśī must be present during madhyāhna. It covers 0 of 48 minutes on the 13th and 48 of 48 on the 14th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 8391 s"
        },
        {
          "step": "ruling",
          "text": "Śrī Rāma Dvādaśī, Harbin, 1981: Sunday 14 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shri-rama-dvadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 12 Sri Rama dvadasi (purvaviddha), Campaka dvadasi (Orissa) (purvaviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-14",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-14",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śrī Rāma Dvādaśī 1981 falls on Sunday 14 June. Dvādaśī runs from 14:17 on Sat 13 Jun to 16:41 on Sun 14 Jun and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shri-rama-dvadashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-06-14",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-14",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1398,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-06-14T16:41:10+08:00",
          "utc": "1981-06-14T08:41:10Z",
          "ms": 361356069912.9576
        },
        "end": {
          "local": "1981-06-15T19:00:59+08:00",
          "utc": "1981-06-15T11:00:59Z",
          "ms": 361450858953.40735
        },
        "month": {
          "amanta": 2,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-14T16:41:10+08:00",
          "utc": "1981-06-14T08:41:10Z",
          "ms": 361356069912.9576
        },
        "end": {
          "local": "1981-06-15T19:00:59+08:00",
          "utc": "1981-06-15T11:00:59Z",
          "ms": 361450858953.40735
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-06-14",
          "window": {
            "start": {
              "local": "1981-06-14T19:23:49+08:00",
              "utc": "1981-06-14T11:23:49Z",
              "ms": 361365829361.5821
            },
            "end": {
              "local": "1981-06-14T20:30:25+08:00",
              "utc": "1981-06-14T12:30:25Z",
              "ms": 361369825119.72614
            }
          },
          "covered_min": 67,
          "window_min": 67,
          "qualifies": true
        },
        {
          "local_date": "1981-06-15",
          "window": {
            "start": {
              "local": "1981-06-15T19:24:17+08:00",
              "utc": "1981-06-15T11:24:17Z",
              "ms": 361452256877.3353
            },
            "end": {
              "local": "1981-06-15T20:30:49+08:00",
              "utc": "1981-06-15T12:30:49Z",
              "ms": 361456248781.7318
            }
          },
          "covered_min": 0,
          "window_min": 67,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 16:41 on Sun 14 Jun to 19:01 on Mon 15 Jun.",
          "fact": "1981-06-14T08:41:10Z → 1981-06-15T11:00:59Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 19:24–20:30 on the 14th, 19:24–20:31 on the 15th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 67 of 67 minutes on the 14th and 0 of 67 on the 15th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 1398 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Sunday 14 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-14",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-14",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Sunday 14 June. Trayodaśī runs from 16:41 on Sun 14 Jun to 19:01 on Mon 15 Jun and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-06-14",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vata-savitri-vrata",
      "festival": "vata-savitri-vrata",
      "name": "Vaṭa Sāvitrī Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-17",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2347,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-06-16T21:10:18+08:00",
          "utc": "1981-06-16T13:10:18Z",
          "ms": 361545018192.15784
        },
        "end": {
          "local": "1981-06-17T23:04:27+08:00",
          "utc": "1981-06-17T15:04:27Z",
          "ms": 361638267429.4124
        },
        "month": {
          "amanta": 2,
          "purnimanta": 2,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Jyeṣṭha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-16T21:10:18+08:00",
          "utc": "1981-06-16T13:10:18Z",
          "ms": 361545018192.15784
        },
        "end": {
          "local": "1981-06-17T23:04:27+08:00",
          "utc": "1981-06-17T15:04:27Z",
          "ms": 361638267429.4124
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-06-16",
          "window": {
            "start": {
              "local": "1981-06-16T19:24:42+08:00",
              "utc": "1981-06-16T11:24:42Z",
              "ms": 361538682233.00543
            },
            "end": {
              "local": "1981-06-16T20:31:11+08:00",
              "utc": "1981-06-16T12:31:11Z",
              "ms": 361542670886.6152
            }
          },
          "covered_min": 0,
          "window_min": 66,
          "qualifies": false
        },
        {
          "local_date": "1981-06-17",
          "window": {
            "start": {
              "local": "1981-06-17T19:25:05+08:00",
              "utc": "1981-06-17T11:25:05Z",
              "ms": 361625105398.4148
            },
            "end": {
              "local": "1981-06-17T20:31:31+08:00",
              "utc": "1981-06-17T12:31:31Z",
              "ms": 361629091406.87524
            }
          },
          "covered_min": 66,
          "window_min": 66,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 21:10 on Tue 16 Jun to 23:04 on Wed 17 Jun.",
          "fact": "1981-06-16T13:10:18Z → 1981-06-17T15:04:27Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 19:25–20:31 on the 16th, 19:25–20:32 on the 17th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during pradoṣa. It covers 0 of 66 minutes on the 16th and 66 of 66 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 2347 s"
        },
        {
          "step": "ruling",
          "text": "Vaṭa Sāvitrī Vrata, Harbin, 1981: Wednesday 17 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vata-savitri-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Vata-savitri vrata (Deccan) (pradosavyapini, purvaviddha), Snanayatra (Bengal & Orissa) (paraviddha)."
          }
        ],
        "kaala": "pradosha",
        "priority": "purvaviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-17",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-17",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vaṭa Sāvitrī Vrata 1981 falls on Wednesday 17 June. Pūrṇimā runs from 21:10 on Tue 16 Jun to 23:04 on Wed 17 Jun and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vata-savitri-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-06-21",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-21",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 18051,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-06-21T02:43:49+08:00",
          "utc": "1981-06-20T18:43:49Z",
          "ms": 361910629455.0219
        },
        "end": {
          "local": "1981-06-22T03:06:48+08:00",
          "utc": "1981-06-21T19:06:48Z",
          "ms": 361998407561.7021
        },
        "month": {
          "amanta": 2,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-21T02:43:49+08:00",
          "utc": "1981-06-20T18:43:49Z",
          "ms": 361910629455.0219
        },
        "end": {
          "local": "1981-06-22T03:06:48+08:00",
          "utc": "1981-06-21T19:06:48Z",
          "ms": 361998407561.7021
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-06-20",
          "window": {
            "start": {
              "local": "1981-06-20T21:26:47+08:00",
              "utc": "1981-06-20T13:26:47Z",
              "ms": 361891606642.36365
            },
            "end": {
              "local": "1981-06-20T21:26:47+08:00",
              "utc": "1981-06-20T13:26:47Z",
              "ms": 361891606642.36365
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-06-21",
          "window": {
            "start": {
              "local": "1981-06-21T22:05:57+08:00",
              "utc": "1981-06-21T14:05:57Z",
              "ms": 361980356572.1723
            },
            "end": {
              "local": "1981-06-21T22:05:57+08:00",
              "utc": "1981-06-21T14:05:57Z",
              "ms": 361980356572.1723
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 02:44 on Sun 21 Jun to 03:07 on Mon 22 Jun.",
          "fact": "1981-06-20T18:43:49Z → 1981-06-21T19:06:48Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 21:27 on the 20th and 22:06 on the 21st.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is not on the 20th and is on the 21st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 18051 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Sunday 21 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-21",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-21",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Sunday 21 June. Caturthī runs from 02:44 on Sun 21 Jun to 03:07 on Mon 22 Jun and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-06-21",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-06-28",
      "festival": "ekadashi",
      "name": "Yoginī Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-28",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 32736,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-06-27T18:40:24+08:00",
          "utc": "1981-06-27T10:40:24Z",
          "ms": 362486423847.2609
        },
        "end": {
          "local": "1981-06-28T15:42:33+08:00",
          "utc": "1981-06-28T07:42:33Z",
          "ms": 362562152990.56976
        },
        "month": {
          "amanta": 2,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-27T18:40:24+08:00",
          "utc": "1981-06-27T10:40:24Z",
          "ms": 362486423847.2609
        },
        "end": {
          "local": "1981-06-28T15:42:33+08:00",
          "utc": "1981-06-28T07:42:33Z",
          "ms": 362562152990.56976
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-06-28",
          "window": {
            "start": {
              "local": "1981-06-28T03:45:59+08:00",
              "utc": "1981-06-27T19:45:59Z",
              "ms": 362519159384.1452
            },
            "end": {
              "local": "1981-06-28T03:45:59+08:00",
              "utc": "1981-06-27T19:45:59Z",
              "ms": 362519159384.1452
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-06-29",
          "window": {
            "start": {
              "local": "1981-06-29T03:46:27+08:00",
              "utc": "1981-06-28T19:46:27Z",
              "ms": 362605587298.1279
            },
            "end": {
              "local": "1981-06-29T03:46:27+08:00",
              "utc": "1981-06-28T19:46:27Z",
              "ms": 362605587298.1279
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 18:40 on Sat 27 Jun to 15:43 on Sun 28 Jun.",
          "fact": "1981-06-27T10:40:24Z → 1981-06-28T07:42:33Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 03:46 on the 28th and 03:46 on the 29th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 28th and is not on the 29th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 32736 s"
        },
        {
          "step": "ruling",
          "text": "Yoginī Ekādaśī, Harbin, 1981: Sunday 28 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-28",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-28",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Yoginī Ekādaśī 1981 falls on Sunday 28 June. Ekādaśī runs from 18:40 on Sat 27 Jun to 15:43 on Sun 28 Jun and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-06-28",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-06-29",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-29",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 24910,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-06-29T12:31:34+08:00",
          "utc": "1981-06-29T04:31:34Z",
          "ms": 362637094303.12115
        },
        "end": {
          "local": "1981-06-30T09:15:30+08:00",
          "utc": "1981-06-30T01:15:30Z",
          "ms": 362711729645.78217
        },
        "month": {
          "amanta": 2,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-29T12:31:34+08:00",
          "utc": "1981-06-29T04:31:34Z",
          "ms": 362637094303.12115
        },
        "end": {
          "local": "1981-06-30T09:15:30+08:00",
          "utc": "1981-06-30T01:15:30Z",
          "ms": 362711729645.78217
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-06-29",
          "window": {
            "start": {
              "local": "1981-06-29T19:26:44+08:00",
              "utc": "1981-06-29T11:26:44Z",
              "ms": 362662004160.01514
            },
            "end": {
              "local": "1981-06-29T20:33:26+08:00",
              "utc": "1981-06-29T12:33:26Z",
              "ms": 362666005906.6389
            }
          },
          "covered_min": 67,
          "window_min": 67,
          "qualifies": true
        },
        {
          "local_date": "1981-06-30",
          "window": {
            "start": {
              "local": "1981-06-30T19:26:37+08:00",
              "utc": "1981-06-30T11:26:37Z",
              "ms": 362748396947.8087
            },
            "end": {
              "local": "1981-06-30T20:33:24+08:00",
              "utc": "1981-06-30T12:33:24Z",
              "ms": 362752403917.8977
            }
          },
          "covered_min": 0,
          "window_min": 67,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 12:32 on Mon 29 Jun to 09:15 on Tue 30 Jun.",
          "fact": "1981-06-29T04:31:34Z → 1981-06-30T01:15:30Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 19:27–20:33 on the 29th, 19:27–20:33 on the 30th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 67 of 67 minutes on the 29th and 0 of 67 on the 30th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 24910 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Monday 29 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-29",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-29",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Monday 29 June. Trayodaśī runs from 12:32 on Mon 29 Jun to 09:15 on Tue 30 Jun and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-06-29",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-06-30",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-06-30",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 21718,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-06-30T09:15:30+08:00",
          "utc": "1981-06-30T01:15:30Z",
          "ms": 362711729645.78217
        },
        "end": {
          "local": "1981-07-01T06:03:01+08:00",
          "utc": "1981-06-30T22:03:01Z",
          "ms": 362786580685.9543
        },
        "month": {
          "amanta": 2,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Jyeṣṭha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-06-30T09:15:30+08:00",
          "utc": "1981-06-30T01:15:30Z",
          "ms": 362711729645.78217
        },
        "end": {
          "local": "1981-07-01T06:03:01+08:00",
          "utc": "1981-06-30T22:03:01Z",
          "ms": 362786580685.9543
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-06-29",
          "window": {
            "start": {
              "local": "1981-06-29T23:12:51+08:00",
              "utc": "1981-06-29T15:12:51Z",
              "ms": 362675570709.85425
            },
            "end": {
              "local": "1981-06-30T00:00:51+08:00",
              "utc": "1981-06-29T16:00:51Z",
              "ms": 362678450709.85425
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-06-30",
          "window": {
            "start": {
              "local": "1981-06-30T23:13:03+08:00",
              "utc": "1981-06-30T15:13:03Z",
              "ms": 362761983085.6425
            },
            "end": {
              "local": "1981-07-01T00:01:03+08:00",
              "utc": "1981-06-30T16:01:03Z",
              "ms": 362764863085.6425
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 09:15 on Tue 30 Jun to 06:03 on Wed 1 Jul.",
          "fact": "1981-06-30T01:15:30Z → 1981-06-30T22:03:01Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:13–00:01 on the 29th, 23:13–00:01 on the 30th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 0 of 48 minutes on the 29th and 48 of 48 on the 30th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 21718 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Tuesday 30 June.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-06-30",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-06-30",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Tuesday 30 June. Caturdaśī runs from 09:15 on Tue 30 Jun to 06:03 on Wed 1 Jul and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-06-30",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/rathayatra",
      "festival": "rathayatra",
      "name": "Rathayātrā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-03",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 36874,
      "anga": {
        "type": "tithi",
        "index": 1,
        "key": "dvitiya",
        "name": "Dvitīyā",
        "start": {
          "local": "1981-07-03T00:24:37+08:00",
          "utc": "1981-07-02T16:24:37Z",
          "ms": 362939077470.83777
        },
        "end": {
          "local": "1981-07-03T22:15:53+08:00",
          "utc": "1981-07-03T14:15:53Z",
          "ms": 363017752644.7174
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-03T00:24:37+08:00",
          "utc": "1981-07-02T16:24:37Z",
          "ms": 362939077470.83777
        },
        "end": {
          "local": "1981-07-03T22:15:53+08:00",
          "utc": "1981-07-03T14:15:53Z",
          "ms": 363017752644.7174
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-07-02",
          "window": {
            "start": {
              "local": "1981-07-02T11:13:08+08:00",
              "utc": "1981-07-02T03:13:08Z",
              "ms": 362891588186.50574
            },
            "end": {
              "local": "1981-07-02T12:01:08+08:00",
              "utc": "1981-07-02T04:01:08Z",
              "ms": 362894468186.50574
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-07-03",
          "window": {
            "start": {
              "local": "1981-07-03T11:13:19+08:00",
              "utc": "1981-07-03T03:13:19Z",
              "ms": 362977998840.9772
            },
            "end": {
              "local": "1981-07-03T12:01:19+08:00",
              "utc": "1981-07-03T04:01:19Z",
              "ms": 362980878840.9772
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvitīyā runs from 00:25 on Fri 3 Jul to 22:16 on Fri 3 Jul.",
          "fact": "1981-07-02T16:24:37Z → 1981-07-03T14:15:53Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:13–12:01 on the 2nd, 11:13–12:01 on the 3rd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvitīyā must be present during madhyāhna. It covers 0 of 48 minutes on the 2nd and 48 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 36874 s"
        },
        {
          "step": "ruling",
          "text": "Rathayātrā, Harbin, 1981: Friday 3 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "rathayatra",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 2 Rathayatra (paraviddha, special when combined with naksatra 'Pusya')"
          }
        ],
        "not_evaluated": "The row calls the day special with Puṣya nakṣatra; the nakṣatra is not tested.",
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-03",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-03",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Rathayātrā 1981 falls on Friday 3 July. Dvitīyā runs from 00:25 on Fri 3 Jul to 22:16 on Fri 3 Jul and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/rathayatra",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-07-05",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-05",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 28350,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-07-04T20:43:58+08:00",
          "utc": "1981-07-04T12:43:58Z",
          "ms": 363098637822.06903
        },
        "end": {
          "local": "1981-07-05T19:54:09+08:00",
          "utc": "1981-07-05T11:54:09Z",
          "ms": 363182049236.04224
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-04T20:43:58+08:00",
          "utc": "1981-07-04T12:43:58Z",
          "ms": 363098637822.06903
        },
        "end": {
          "local": "1981-07-05T19:54:09+08:00",
          "utc": "1981-07-05T11:54:09Z",
          "ms": 363182049236.04224
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-07-04",
          "window": {
            "start": {
              "local": "1981-07-04T11:13:29+08:00",
              "utc": "1981-07-04T03:13:29Z",
              "ms": 363064409203.0759
            },
            "end": {
              "local": "1981-07-04T12:01:29+08:00",
              "utc": "1981-07-04T04:01:29Z",
              "ms": 363067289203.0759
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-07-05",
          "window": {
            "start": {
              "local": "1981-07-05T11:13:39+08:00",
              "utc": "1981-07-05T03:13:39Z",
              "ms": 363150819248.5709
            },
            "end": {
              "local": "1981-07-05T12:01:39+08:00",
              "utc": "1981-07-05T04:01:39Z",
              "ms": 363153699248.5709
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 20:44 on Sat 4 Jul to 19:54 on Sun 5 Jul.",
          "fact": "1981-07-04T12:43:58Z → 1981-07-05T11:54:09Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:13–12:01 on the 4th, 11:14–12:02 on the 5th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 0 of 48 minutes on the 4th and 48 of 48 on the 5th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 28350 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Sunday 5 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-05",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-05",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Sunday 5 July. Caturthī runs from 20:44 on Sat 4 Jul to 19:54 on Sun 5 Jul and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-07-05",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/skanda-panchami",
      "festival": "skanda-panchami",
      "name": "Skanda Pañcamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-06",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 28038,
      "anga": {
        "type": "tithi",
        "index": 4,
        "key": "panchami",
        "name": "Pañcamī",
        "start": {
          "local": "1981-07-05T19:54:09+08:00",
          "utc": "1981-07-05T11:54:09Z",
          "ms": 363182049236.04224
        },
        "end": {
          "local": "1981-07-06T19:49:07+08:00",
          "utc": "1981-07-06T11:49:07Z",
          "ms": 363268147222.3655
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-05T19:54:09+08:00",
          "utc": "1981-07-05T11:54:09Z",
          "ms": 363182049236.04224
        },
        "end": {
          "local": "1981-07-06T19:49:07+08:00",
          "utc": "1981-07-06T11:49:07Z",
          "ms": 363268147222.3655
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-07-05",
          "window": {
            "start": {
              "local": "1981-07-05T11:13:39+08:00",
              "utc": "1981-07-05T03:13:39Z",
              "ms": 363150819248.5709
            },
            "end": {
              "local": "1981-07-05T12:01:39+08:00",
              "utc": "1981-07-05T04:01:39Z",
              "ms": 363153699248.5709
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-07-06",
          "window": {
            "start": {
              "local": "1981-07-06T11:13:49+08:00",
              "utc": "1981-07-06T03:13:49Z",
              "ms": 363237228954.90234
            },
            "end": {
              "local": "1981-07-06T12:01:49+08:00",
              "utc": "1981-07-06T04:01:49Z",
              "ms": 363240108954.90234
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pañcamī runs from 19:54 on Sun 5 Jul to 19:49 on Mon 6 Jul.",
          "fact": "1981-07-05T11:54:09Z → 1981-07-06T11:49:07Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:14–12:02 on the 5th, 11:14–12:02 on the 6th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pañcamī must be present during madhyāhna. It covers 0 of 48 minutes on the 5th and 48 of 48 on the 6th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 28038 s"
        },
        {
          "step": "ruling",
          "text": "Skanda Pañcamī, Harbin, 1981: Monday 6 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "skanda-panchami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 5 Skanda pancami (paraviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-06",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-06",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Skanda Pañcamī 1981 falls on Monday 6 July. Pañcamī runs from 19:54 on Sun 5 Jul to 19:49 on Mon 6 Jul and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/skanda-panchami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vivasvat-saptami",
      "festival": "vivasvat-saptami",
      "name": "Vivasvat Saptamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-08",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 30377,
      "anga": {
        "type": "tithi",
        "index": 6,
        "key": "saptami",
        "name": "Saptamī",
        "start": {
          "local": "1981-07-07T20:28:15+08:00",
          "utc": "1981-07-07T12:28:15Z",
          "ms": 363356894926.3469
        },
        "end": {
          "local": "1981-07-08T21:47:14+08:00",
          "utc": "1981-07-08T13:47:14Z",
          "ms": 363448034084.8695
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-07T20:28:15+08:00",
          "utc": "1981-07-07T12:28:15Z",
          "ms": 363356894926.3469
        },
        "end": {
          "local": "1981-07-08T21:47:14+08:00",
          "utc": "1981-07-08T13:47:14Z",
          "ms": 363448034084.8695
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-07-07",
          "window": {
            "start": {
              "local": "1981-07-07T11:13:58+08:00",
              "utc": "1981-07-07T03:13:58Z",
              "ms": 363323638301.1583
            },
            "end": {
              "local": "1981-07-07T12:01:58+08:00",
              "utc": "1981-07-07T04:01:58Z",
              "ms": 363326518301.1583
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-07-08",
          "window": {
            "start": {
              "local": "1981-07-08T11:14:07+08:00",
              "utc": "1981-07-08T03:14:07Z",
              "ms": 363410047267.9386
            },
            "end": {
              "local": "1981-07-08T12:02:07+08:00",
              "utc": "1981-07-08T04:02:07Z",
              "ms": 363412927267.9386
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Saptamī runs from 20:28 on Tue 7 Jul to 21:47 on Wed 8 Jul.",
          "fact": "1981-07-07T12:28:15Z → 1981-07-08T13:47:14Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:14–12:02 on the 7th, 11:14–12:02 on the 8th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Saptamī must be present during madhyāhna. It covers 0 of 48 minutes on the 7th and 48 of 48 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 30377 s"
        },
        {
          "step": "ruling",
          "text": "Vivasvat Saptamī, Harbin, 1981: Wednesday 8 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vivasvat-saptami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 7 Vivasvat saptami (purvaviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-08",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-08",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vivasvat Saptamī 1981 falls on Wednesday 8 July. Saptamī runs from 20:28 on Tue 7 Jul to 21:47 on Wed 8 Jul and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vivasvat-saptami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-07-13",
      "festival": "ekadashi",
      "name": "Hariśayanī Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-13",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1015,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-07-12T04:12:13+08:00",
          "utc": "1981-07-11T20:12:13Z",
          "ms": 363730333292.03796
        },
        "end": {
          "local": "1981-07-13T06:31:27+08:00",
          "utc": "1981-07-12T22:31:27Z",
          "ms": 363825087316.67865
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-12T04:12:13+08:00",
          "utc": "1981-07-11T20:12:13Z",
          "ms": 363730333292.03796
        },
        "end": {
          "local": "1981-07-13T06:31:27+08:00",
          "utc": "1981-07-12T22:31:27Z",
          "ms": 363825087316.67865
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-07-12",
          "window": {
            "start": {
              "local": "1981-07-12T03:55:18+08:00",
              "utc": "1981-07-11T19:55:18Z",
              "ms": 363729317909.45685
            },
            "end": {
              "local": "1981-07-12T03:55:18+08:00",
              "utc": "1981-07-11T19:55:18Z",
              "ms": 363729317909.45685
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-07-13",
          "window": {
            "start": {
              "local": "1981-07-13T03:56:10+08:00",
              "utc": "1981-07-12T19:56:10Z",
              "ms": 363815770040.2388
            },
            "end": {
              "local": "1981-07-13T03:56:10+08:00",
              "utc": "1981-07-12T19:56:10Z",
              "ms": 363815770040.2388
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 04:12 on Sun 12 Jul to 06:31 on Mon 13 Jul.",
          "fact": "1981-07-11T20:12:13Z → 1981-07-12T22:31:27Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 03:55 on the 12th and 03:56 on the 13th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 12th and is on the 13th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 1015 s"
        },
        {
          "step": "ruling",
          "text": "Hariśayanī Ekādaśī, Harbin, 1981: Monday 13 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-13",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-13",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Hariśayanī Ekādaśī 1981 falls on Monday 13 July. Ekādaśī runs from 04:12 on Sun 12 Jul to 06:31 on Mon 13 Jul and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-07-13",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-07-14",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-14",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 32131,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-07-14T08:38:05+08:00",
          "utc": "1981-07-14T00:38:05Z",
          "ms": 363919085335.43713
        },
        "end": {
          "local": "1981-07-15T10:24:27+08:00",
          "utc": "1981-07-15T02:24:27Z",
          "ms": 364011866686.38385
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-14T08:38:05+08:00",
          "utc": "1981-07-14T00:38:05Z",
          "ms": 363919085335.43713
        },
        "end": {
          "local": "1981-07-15T10:24:27+08:00",
          "utc": "1981-07-15T02:24:27Z",
          "ms": 364011866686.38385
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-07-14",
          "window": {
            "start": {
              "local": "1981-07-14T19:20:41+08:00",
              "utc": "1981-07-14T11:20:41Z",
              "ms": 363957640820.3714
            },
            "end": {
              "local": "1981-07-14T20:29:39+08:00",
              "utc": "1981-07-14T12:29:39Z",
              "ms": 363961779152.5963
            }
          },
          "covered_min": 69,
          "window_min": 69,
          "qualifies": true
        },
        {
          "local_date": "1981-07-15",
          "window": {
            "start": {
              "local": "1981-07-15T19:19:58+08:00",
              "utc": "1981-07-15T11:19:58Z",
              "ms": 364043997774.0922
            },
            "end": {
              "local": "1981-07-15T20:29:09+08:00",
              "utc": "1981-07-15T12:29:09Z",
              "ms": 364048149318.0703
            }
          },
          "covered_min": 0,
          "window_min": 69,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 08:38 on Tue 14 Jul to 10:24 on Wed 15 Jul.",
          "fact": "1981-07-14T00:38:05Z → 1981-07-15T02:24:27Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 19:21–20:30 on the 14th, 19:20–20:29 on the 15th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 69 of 69 minutes on the 14th and 0 of 69 on the 15th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 32131 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Tuesday 14 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-14",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-14",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Tuesday 14 July. Trayodaśī runs from 08:38 on Tue 14 Jul to 10:24 on Wed 15 Jul and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-07-14",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/kokila-vrata",
      "festival": "kokila-vrata",
      "name": "Kokilā Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 12953,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-07-16T11:45:33+08:00",
          "utc": "1981-07-16T03:45:33Z",
          "ms": 364103132563.0618
        },
        "end": {
          "local": "1981-07-17T12:38:49+08:00",
          "utc": "1981-07-17T04:38:49Z",
          "ms": 364192729254.3843
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-16T11:45:33+08:00",
          "utc": "1981-07-16T03:45:33Z",
          "ms": 364103132563.0618
        },
        "end": {
          "local": "1981-07-17T12:38:49+08:00",
          "utc": "1981-07-17T04:38:49Z",
          "ms": 364192729254.3843
        }
      },
      "kaala": "sayahna",
      "days": [
        {
          "local_date": "1981-07-16",
          "window": {
            "start": {
              "local": "1981-07-16T16:15:09+08:00",
              "utc": "1981-07-16T08:15:09Z",
              "ms": 364119308862.93524
            },
            "end": {
              "local": "1981-07-16T19:19:12+08:00",
              "utc": "1981-07-16T11:19:12Z",
              "ms": 364130352490.187
            }
          },
          "covered_min": 184,
          "window_min": 184,
          "qualifies": true
        },
        {
          "local_date": "1981-07-17",
          "window": {
            "start": {
              "local": "1981-07-17T16:14:42+08:00",
              "utc": "1981-07-17T08:14:42Z",
              "ms": 364205682319.5085
            },
            "end": {
              "local": "1981-07-17T19:18:25+08:00",
              "utc": "1981-07-17T11:18:25Z",
              "ms": 364216704999.0114
            }
          },
          "covered_min": 0,
          "window_min": 184,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 11:46 on Thu 16 Jul to 12:39 on Fri 17 Jul.",
          "fact": "1981-07-16T03:45:33Z → 1981-07-17T04:38:49Z"
        },
        {
          "step": "kaala",
          "text": "Sāyāhna is last 3 of 15 day muhūrtas: 16:15–19:19 on the 16th, 16:15–19:18 on the 17th.",
          "fact": "sayahna: day-muhurta-13-15 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during sāyāhna. It covers 184 of 184 minutes on the 16th and 0 of 184 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one late afternoon qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 12953 s"
        },
        {
          "step": "ruling",
          "text": "Kokilā Vrata, Harbin, 1981: Thursday 16 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "kokila-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Guru purnima (paraviddha), Vyasa puja (paraviddha, 3 muhurtas after sunrise), Kokila vrata (sayahna vyapini). Siva sayanotsava (pradosavyapini)."
          }
        ],
        "kaala": "sayahna",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kokilā Vrata 1981 falls on Thursday 16 July. Pūrṇimā runs from 11:46 on Thu 16 Jul to 12:39 on Fri 17 Jul and covers all of sāyāhna that late afternoon.",
      "cite": "https://ahargana.org/harbin/festivals/1981/kokila-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shiva-shayanotsava",
      "festival": "shiva-shayanotsava",
      "name": "Śiva Śayanotsava",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 23976,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-07-16T11:45:33+08:00",
          "utc": "1981-07-16T03:45:33Z",
          "ms": 364103132563.0618
        },
        "end": {
          "local": "1981-07-17T12:38:49+08:00",
          "utc": "1981-07-17T04:38:49Z",
          "ms": 364192729254.3843
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-16T11:45:33+08:00",
          "utc": "1981-07-16T03:45:33Z",
          "ms": 364103132563.0618
        },
        "end": {
          "local": "1981-07-17T12:38:49+08:00",
          "utc": "1981-07-17T04:38:49Z",
          "ms": 364192729254.3843
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-07-16",
          "window": {
            "start": {
              "local": "1981-07-16T19:19:12+08:00",
              "utc": "1981-07-16T11:19:12Z",
              "ms": 364130352490.187
            },
            "end": {
              "local": "1981-07-16T20:28:38+08:00",
              "utc": "1981-07-16T12:28:38Z",
              "ms": 364134517705.0283
            }
          },
          "covered_min": 69,
          "window_min": 69,
          "qualifies": true
        },
        {
          "local_date": "1981-07-17",
          "window": {
            "start": {
              "local": "1981-07-17T19:18:25+08:00",
              "utc": "1981-07-17T11:18:25Z",
              "ms": 364216704999.0114
            },
            "end": {
              "local": "1981-07-17T20:28:04+08:00",
              "utc": "1981-07-17T12:28:04Z",
              "ms": 364220884333.42975
            }
          },
          "covered_min": 0,
          "window_min": 70,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 11:46 on Thu 16 Jul to 12:39 on Fri 17 Jul.",
          "fact": "1981-07-16T03:45:33Z → 1981-07-17T04:38:49Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 19:19–20:29 on the 16th, 19:18–20:28 on the 17th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during pradoṣa. It covers 69 of 69 minutes on the 16th and 0 of 70 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 23976 s"
        },
        {
          "step": "ruling",
          "text": "Śiva Śayanotsava, Harbin, 1981: Thursday 16 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shiva-shayanotsava",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Guru purnima (paraviddha), Vyasa puja (paraviddha, 3 muhurtas after sunrise), Kokila vrata (sayahna vyapini). Siva sayanotsava (pradosavyapini)."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śiva Śayanotsava 1981 falls on Thursday 16 July. Pūrṇimā runs from 11:46 on Thu 16 Jul to 12:39 on Fri 17 Jul and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shiva-shayanotsava",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vyasa-puja",
      "festival": "vyasa-puja",
      "name": "Vyāsa Pūjā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-17",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 16955,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-07-16T11:45:33+08:00",
          "utc": "1981-07-16T03:45:33Z",
          "ms": 364103132563.0618
        },
        "end": {
          "local": "1981-07-17T12:38:49+08:00",
          "utc": "1981-07-17T04:38:49Z",
          "ms": 364192729254.3843
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-16T11:45:33+08:00",
          "utc": "1981-07-16T03:45:33Z",
          "ms": 364103132563.0618
        },
        "end": {
          "local": "1981-07-17T12:38:49+08:00",
          "utc": "1981-07-17T04:38:49Z",
          "ms": 364192729254.3843
        }
      },
      "kaala": "udaya-3",
      "days": [
        {
          "local_date": "1981-07-16",
          "window": {
            "start": {
              "local": "1981-07-16T03:58:54+08:00",
              "utc": "1981-07-15T19:58:54Z",
              "ms": 364075134353.92804
            },
            "end": {
              "local": "1981-07-16T07:02:58+08:00",
              "utc": "1981-07-15T23:02:58Z",
              "ms": 364086177981.1798
            }
          },
          "covered_min": 0,
          "window_min": 184,
          "qualifies": false
        },
        {
          "local_date": "1981-07-17",
          "window": {
            "start": {
              "local": "1981-07-17T03:59:52+08:00",
              "utc": "1981-07-16T19:59:52Z",
              "ms": 364161591601.49677
            },
            "end": {
              "local": "1981-07-17T07:03:34+08:00",
              "utc": "1981-07-16T23:03:34Z",
              "ms": 364172614280.9997
            }
          },
          "covered_min": 184,
          "window_min": 184,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 11:46 on Thu 16 Jul to 12:39 on Fri 17 Jul.",
          "fact": "1981-07-16T03:45:33Z → 1981-07-17T04:38:49Z"
        },
        {
          "step": "kaala",
          "text": "The first three muhūrtas after sunrise is first 3 of 15 day muhūrtas: 03:59–07:03 on the 16th, 04:00–07:04 on the 17th.",
          "fact": "udaya-3: day-muhurta-1-3 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must hold through the first three muhūrtas after sunrise. It covers 0 of 184 minutes on the 16th and 184 of 184 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one morning qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 16955 s"
        },
        {
          "step": "ruling",
          "text": "Vyāsa Pūjā, Harbin, 1981: Friday 17 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vyasa-puja",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Guru purnima (paraviddha), Vyasa puja (paraviddha, 3 muhurtas after sunrise), Kokila vrata (sayahna vyapini). Siva sayanotsava (pradosavyapini)."
          }
        ],
        "kaala": "udaya-3",
        "priority": "paraviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-17",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-17",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vyāsa Pūjā 1981 falls on Friday 17 July. Pūrṇimā runs from 11:46 on Thu 16 Jul to 12:39 on Fri 17 Jul and covers all of the first three muhūrtas after sunrise that morning.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vyasa-puja",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/guru-purnima",
      "festival": "guru-purnima",
      "name": "Guru Pūrṇimā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-17",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1051,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-07-16T11:45:33+08:00",
          "utc": "1981-07-16T03:45:33Z",
          "ms": 364103132563.0618
        },
        "end": {
          "local": "1981-07-17T12:38:49+08:00",
          "utc": "1981-07-17T04:38:49Z",
          "ms": 364192729254.3843
        },
        "month": {
          "amanta": 3,
          "purnimanta": 3,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Āṣāḍha"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-16T11:45:33+08:00",
          "utc": "1981-07-16T03:45:33Z",
          "ms": 364103132563.0618
        },
        "end": {
          "local": "1981-07-17T12:38:49+08:00",
          "utc": "1981-07-17T04:38:49Z",
          "ms": 364192729254.3843
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-07-16",
          "window": {
            "start": {
              "local": "1981-07-16T11:15:03+08:00",
              "utc": "1981-07-16T03:15:03Z",
              "ms": 364101303422.0575
            },
            "end": {
              "local": "1981-07-16T12:03:03+08:00",
              "utc": "1981-07-16T04:03:03Z",
              "ms": 364104183422.0575
            }
          },
          "covered_min": 18,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-07-17",
          "window": {
            "start": {
              "local": "1981-07-17T11:15:08+08:00",
              "utc": "1981-07-17T03:15:08Z",
              "ms": 364187708300.2541
            },
            "end": {
              "local": "1981-07-17T12:03:08+08:00",
              "utc": "1981-07-17T04:03:08Z",
              "ms": 364190588300.2541
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "paraviddha",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 11:46 on Thu 16 Jul to 12:39 on Fri 17 Jul.",
          "fact": "1981-07-16T03:45:33Z → 1981-07-17T04:38:49Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:15–12:03 on the 16th, 11:15–12:03 on the 17th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during madhyāhna. It covers 18 of 48 minutes on the 16th and 48 of 48 on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Both middays qualify. Paraviddhā: the second is taken.",
          "fact": "priority: paraviddha → paraviddha · margin 1051 s"
        },
        {
          "step": "ruling",
          "text": "Guru Pūrṇimā, Harbin, 1981: Friday 17 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "guru-purnima",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Guru purnima (paraviddha), Vyasa puja (paraviddha, 3 muhurtas after sunrise), Kokila vrata (sayahna vyapini). Siva sayanotsava (pradosavyapini)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-17",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-17",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Guru Pūrṇimā 1981 falls on Friday 17 July. Pūrṇimā runs from 11:46 on Thu 16 Jul to 12:39 on Fri 17 Jul and covers all of madhyāhna that midday. It also reaches the previous midday for 18 minutes; by the rule the second midday is taken.",
      "cite": "https://ahargana.org/harbin/festivals/1981/guru-purnima",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ashunya-shayana-vrata-ashadha",
      "festival": "ashunya-shayana-vrata-ashadha",
      "name": "Aśūnya Śayana Vrata (Āṣāḍha)",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-18",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 25364,
      "anga": {
        "type": "tithi",
        "index": 16,
        "key": "dvitiya",
        "name": "Dvitīyā",
        "start": {
          "local": "1981-07-18T13:03:35+08:00",
          "utc": "1981-07-18T05:03:35Z",
          "ms": 364280615373.0386
        },
        "end": {
          "local": "1981-07-19T13:00:26+08:00",
          "utc": "1981-07-19T05:00:26Z",
          "ms": 364366825869.55554
        },
        "month": {
          "amanta": 3,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-18T13:03:35+08:00",
          "utc": "1981-07-18T05:03:35Z",
          "ms": 364280615373.0386
        },
        "end": {
          "local": "1981-07-19T13:00:26+08:00",
          "utc": "1981-07-19T05:00:26Z",
          "ms": 364366825869.55554
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-07-18",
          "window": {
            "start": {
              "local": "1981-07-18T20:06:19+08:00",
              "utc": "1981-07-18T12:06:19Z",
              "ms": 364305979238.5171
            },
            "end": {
              "local": "1981-07-18T20:06:19+08:00",
              "utc": "1981-07-18T12:06:19Z",
              "ms": 364305979238.5171
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-07-19",
          "window": {
            "start": {
              "local": "1981-07-19T20:42:51+08:00",
              "utc": "1981-07-19T12:42:51Z",
              "ms": 364394570524.6235
            },
            "end": {
              "local": "1981-07-19T20:42:51+08:00",
              "utc": "1981-07-19T12:42:51Z",
              "ms": 364394570524.6235
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvitīyā runs from 13:04 on Sat 18 Jul to 13:00 on Sun 19 Jul.",
          "fact": "1981-07-18T05:03:35Z → 1981-07-19T05:00:26Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 20:06 on the 18th and 20:43 on the 19th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Dvitīyā must be current at moonrise. It is on the 18th and is not on the 19th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 25364 s"
        },
        {
          "step": "ruling",
          "text": "Aśūnya Śayana Vrata (Āṣāḍha), Harbin, 1981: Saturday 18 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ashunya-shayana-vrata-ashadha",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 102",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 2 Asunya sayana vrata (candrodaya vyapini; purvahna vyapini and purvaviddha in Bengal)."
          }
        ],
        "not_evaluated": "In Bengal the row reads pūrvāhṇa and pūrvaviddha; that reading is not applied.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-18",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-18",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Aśūnya Śayana Vrata (Āṣāḍha) 1981 falls on Saturday 18 July. Dvitīyā runs from 13:04 on Sat 18 Jul to 13:00 on Sun 19 Jul and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ashunya-shayana-vrata-ashadha",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-07-20",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-20",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 31473,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-07-20T12:30:41+08:00",
          "utc": "1981-07-20T04:30:41Z",
          "ms": 364451441364.97534
        },
        "end": {
          "local": "1981-07-21T11:36:07+08:00",
          "utc": "1981-07-21T03:36:07Z",
          "ms": 364534566888.55975
        },
        "month": {
          "amanta": 3,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-20T12:30:41+08:00",
          "utc": "1981-07-20T04:30:41Z",
          "ms": 364451441364.97534
        },
        "end": {
          "local": "1981-07-21T11:36:07+08:00",
          "utc": "1981-07-21T03:36:07Z",
          "ms": 364534566888.55975
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-07-20",
          "window": {
            "start": {
              "local": "1981-07-20T21:15:14+08:00",
              "utc": "1981-07-20T13:15:14Z",
              "ms": 364482914432.05414
            },
            "end": {
              "local": "1981-07-20T21:15:14+08:00",
              "utc": "1981-07-20T13:15:14Z",
              "ms": 364482914432.05414
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-07-21",
          "window": {
            "start": {
              "local": "1981-07-21T21:44:48+08:00",
              "utc": "1981-07-21T13:44:48Z",
              "ms": 364571087831.0132
            },
            "end": {
              "local": "1981-07-21T21:44:48+08:00",
              "utc": "1981-07-21T13:44:48Z",
              "ms": 364571087831.0132
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 12:31 on Mon 20 Jul to 11:36 on Tue 21 Jul.",
          "fact": "1981-07-20T04:30:41Z → 1981-07-21T03:36:07Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 21:15 on the 20th and 21:45 on the 21st.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is on the 20th and is not on the 21st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 31473 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Monday 20 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-20",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-20",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Monday 20 July. Caturthī runs from 12:31 on Mon 20 Jul to 11:36 on Tue 21 Jul and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-07-20",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-07-27",
      "festival": "ekadashi",
      "name": "Kāmikā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-27",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 16482,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-07-26T23:35:38+08:00",
          "utc": "1981-07-26T15:35:38Z",
          "ms": 365009738348.60425
        },
        "end": {
          "local": "1981-07-27T20:59:34+08:00",
          "utc": "1981-07-27T12:59:34Z",
          "ms": 365086773837.5726
        },
        "month": {
          "amanta": 3,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-26T23:35:38+08:00",
          "utc": "1981-07-26T15:35:38Z",
          "ms": 365009738348.60425
        },
        "end": {
          "local": "1981-07-27T20:59:34+08:00",
          "utc": "1981-07-27T12:59:34Z",
          "ms": 365086773837.5726
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-07-27",
          "window": {
            "start": {
              "local": "1981-07-27T04:10:20+08:00",
              "utc": "1981-07-26T20:10:20Z",
              "ms": 365026220294.58984
            },
            "end": {
              "local": "1981-07-27T04:10:20+08:00",
              "utc": "1981-07-26T20:10:20Z",
              "ms": 365026220294.58984
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-07-28",
          "window": {
            "start": {
              "local": "1981-07-28T04:11:28+08:00",
              "utc": "1981-07-27T20:11:28Z",
              "ms": 365112687797.92896
            },
            "end": {
              "local": "1981-07-28T04:11:28+08:00",
              "utc": "1981-07-27T20:11:28Z",
              "ms": 365112687797.92896
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 23:36 on Sun 26 Jul to 21:00 on Mon 27 Jul.",
          "fact": "1981-07-26T15:35:38Z → 1981-07-27T12:59:34Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 04:10 on the 27th and 04:11 on the 28th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 27th and is not on the 28th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 16482 s"
        },
        {
          "step": "ruling",
          "text": "Kāmikā Ekādaśī, Harbin, 1981: Monday 27 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-27",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-27",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kāmikā Ekādaśī 1981 falls on Monday 27 July. Ekādaśī runs from 23:36 on Sun 26 Jul to 21:00 on Mon 27 Jul and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-07-27",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-07-28",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-28",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2541,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-07-28T18:25:06+08:00",
          "utc": "1981-07-28T10:25:06Z",
          "ms": 365163905502.4758
        },
        "end": {
          "local": "1981-07-29T15:58:05+08:00",
          "utc": "1981-07-29T07:58:05Z",
          "ms": 365241485342.8578
        },
        "month": {
          "amanta": 3,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-28T18:25:06+08:00",
          "utc": "1981-07-28T10:25:06Z",
          "ms": 365163905502.4758
        },
        "end": {
          "local": "1981-07-29T15:58:05+08:00",
          "utc": "1981-07-29T07:58:05Z",
          "ms": 365241485342.8578
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-07-28",
          "window": {
            "start": {
              "local": "1981-07-28T19:07:26+08:00",
              "utc": "1981-07-28T11:07:26Z",
              "ms": 365166446364.1822
            },
            "end": {
              "local": "1981-07-28T20:20:08+08:00",
              "utc": "1981-07-28T12:20:08Z",
              "ms": 365170807643.59906
            }
          },
          "covered_min": 73,
          "window_min": 73,
          "qualifies": true
        },
        {
          "local_date": "1981-07-29",
          "window": {
            "start": {
              "local": "1981-07-29T19:06:15+08:00",
              "utc": "1981-07-29T11:06:15Z",
              "ms": 365252774989.43
            },
            "end": {
              "local": "1981-07-29T20:19:15+08:00",
              "utc": "1981-07-29T12:19:15Z",
              "ms": 365257154955.251
            }
          },
          "covered_min": 0,
          "window_min": 73,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 18:25 on Tue 28 Jul to 15:58 on Wed 29 Jul.",
          "fact": "1981-07-28T10:25:06Z → 1981-07-29T07:58:05Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 19:07–20:20 on the 28th, 19:06–20:19 on the 29th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 73 of 73 minutes on the 28th and 0 of 73 on the 29th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 2541 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Tuesday 28 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-28",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-28",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Tuesday 28 July. Trayodaśī runs from 18:25 on Tue 28 Jul to 15:58 on Wed 29 Jul and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-07-28",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-07-29",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-07-29",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 26275,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-07-29T15:58:05+08:00",
          "utc": "1981-07-29T07:58:05Z",
          "ms": 365241485342.8578
        },
        "end": {
          "local": "1981-07-30T13:44:52+08:00",
          "utc": "1981-07-30T05:44:52Z",
          "ms": 365319892038.3763
        },
        "month": {
          "amanta": 3,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Āṣāḍha",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-07-29T15:58:05+08:00",
          "utc": "1981-07-29T07:58:05Z",
          "ms": 365241485342.8578
        },
        "end": {
          "local": "1981-07-30T13:44:52+08:00",
          "utc": "1981-07-30T05:44:52Z",
          "ms": 365319892038.3763
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-07-29",
          "window": {
            "start": {
              "local": "1981-07-29T23:16:00+08:00",
              "utc": "1981-07-29T15:16:00Z",
              "ms": 365267759861.25854
            },
            "end": {
              "local": "1981-07-30T00:04:00+08:00",
              "utc": "1981-07-29T16:04:00Z",
              "ms": 365270639861.25854
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-07-30",
          "window": {
            "start": {
              "local": "1981-07-30T23:15:58+08:00",
              "utc": "1981-07-30T15:15:58Z",
              "ms": 365354157957.7211
            },
            "end": {
              "local": "1981-07-31T00:03:58+08:00",
              "utc": "1981-07-30T16:03:58Z",
              "ms": 365357037957.7211
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 15:58 on Wed 29 Jul to 13:45 on Thu 30 Jul.",
          "fact": "1981-07-29T07:58:05Z → 1981-07-30T05:44:52Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:16–00:04 on the 29th, 23:16–00:04 on the 30th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 48 of 48 minutes on the 29th and 0 of 48 on the 30th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 26275 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Wednesday 29 July.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-07-29",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-07-29",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Wednesday 29 July. Caturdaśī runs from 15:58 on Wed 29 Jul to 13:45 on Thu 30 Jul and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-07-29",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/madhusrava-tritiya",
      "festival": "madhusrava-tritiya",
      "name": "Madhusravā Tṛtīyā",
      "everyday": "Hariyali Teej",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-02",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 6199,
      "anga": {
        "type": "tithi",
        "index": 2,
        "key": "tritiya",
        "name": "Tṛtīyā",
        "start": {
          "local": "1981-08-02T09:31:54+08:00",
          "utc": "1981-08-02T01:31:54Z",
          "ms": 365563913761.8899
        },
        "end": {
          "local": "1981-08-03T09:15:00+08:00",
          "utc": "1981-08-03T01:15:00Z",
          "ms": 365649299747.0924
        },
        "month": {
          "amanta": 4,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-02T09:31:54+08:00",
          "utc": "1981-08-02T01:31:54Z",
          "ms": 365563913761.8899
        },
        "end": {
          "local": "1981-08-03T09:15:00+08:00",
          "utc": "1981-08-03T01:15:00Z",
          "ms": 365649299747.0924
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-02",
          "window": {
            "start": {
              "local": "1981-08-02T11:15:13+08:00",
              "utc": "1981-08-02T03:15:13Z",
              "ms": 365570113187.18494
            },
            "end": {
              "local": "1981-08-02T12:03:13+08:00",
              "utc": "1981-08-02T04:03:13Z",
              "ms": 365572993187.18494
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-08-03",
          "window": {
            "start": {
              "local": "1981-08-03T11:15:09+08:00",
              "utc": "1981-08-03T03:15:09Z",
              "ms": 365656508622.6953
            },
            "end": {
              "local": "1981-08-03T12:03:09+08:00",
              "utc": "1981-08-03T04:03:09Z",
              "ms": 365659388622.6953
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Tṛtīyā runs from 09:32 on Sun 2 Aug to 09:15 on Mon 3 Aug.",
          "fact": "1981-08-02T01:31:54Z → 1981-08-03T01:15:00Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:15–12:03 on the 2nd, 11:15–12:03 on the 3rd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Tṛtīyā must be present during madhyāhna. It covers 48 of 48 minutes on the 2nd and 0 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 6199 s"
        },
        {
          "step": "ruling",
          "text": "Madhusravā Tṛtīyā, Harbin, 1981: Sunday 2 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "madhusrava-tritiya",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 3 Madhusrava (Gujerat) (paraviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Madhusravā Tṛtīyā (Hariyali Teej) 1981 falls on Sunday 2 August. Tṛtīyā runs from 09:32 on Sun 2 Aug to 09:15 on Mon 3 Aug and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/madhusrava-tritiya",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-08-03",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-03",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 5858,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-08-03T09:15:00+08:00",
          "utc": "1981-08-03T01:15:00Z",
          "ms": 365649299747.0924
        },
        "end": {
          "local": "1981-08-04T09:37:25+08:00",
          "utc": "1981-08-04T01:37:25Z",
          "ms": 365737045011.0882
        },
        "month": {
          "amanta": 4,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-03T09:15:00+08:00",
          "utc": "1981-08-03T01:15:00Z",
          "ms": 365649299747.0924
        },
        "end": {
          "local": "1981-08-04T09:37:25+08:00",
          "utc": "1981-08-04T01:37:25Z",
          "ms": 365737045011.0882
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-03",
          "window": {
            "start": {
              "local": "1981-08-03T11:15:09+08:00",
              "utc": "1981-08-03T03:15:09Z",
              "ms": 365656508622.6953
            },
            "end": {
              "local": "1981-08-03T12:03:09+08:00",
              "utc": "1981-08-03T04:03:09Z",
              "ms": 365659388622.6953
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-08-04",
          "window": {
            "start": {
              "local": "1981-08-04T11:15:03+08:00",
              "utc": "1981-08-04T03:15:03Z",
              "ms": 365742903454.93933
            },
            "end": {
              "local": "1981-08-04T12:03:03+08:00",
              "utc": "1981-08-04T04:03:03Z",
              "ms": 365745783454.93933
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 09:15 on Mon 3 Aug to 09:37 on Tue 4 Aug.",
          "fact": "1981-08-03T01:15:00Z → 1981-08-04T01:37:25Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:15–12:03 on the 3rd, 11:15–12:03 on the 4th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 48 of 48 minutes on the 3rd and 0 of 48 on the 4th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 5858 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Monday 3 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-03",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-03",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Monday 3 August. Caturthī runs from 09:15 on Mon 3 Aug to 09:37 on Tue 4 Aug and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-08-03",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/naga-panchami",
      "festival": "naga-panchami",
      "name": "Nāga Pañcamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-04",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2177,
      "anga": {
        "type": "tithi",
        "index": 4,
        "key": "panchami",
        "name": "Pañcamī",
        "start": {
          "local": "1981-08-04T09:37:25+08:00",
          "utc": "1981-08-04T01:37:25Z",
          "ms": 365737045011.0882
        },
        "end": {
          "local": "1981-08-05T10:38:41+08:00",
          "utc": "1981-08-05T02:38:41Z",
          "ms": 365827120732.7763
        },
        "month": {
          "amanta": 4,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-04T09:37:25+08:00",
          "utc": "1981-08-04T01:37:25Z",
          "ms": 365737045011.0882
        },
        "end": {
          "local": "1981-08-05T10:38:41+08:00",
          "utc": "1981-08-05T02:38:41Z",
          "ms": 365827120732.7763
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-04",
          "window": {
            "start": {
              "local": "1981-08-04T11:15:03+08:00",
              "utc": "1981-08-04T03:15:03Z",
              "ms": 365742903454.93933
            },
            "end": {
              "local": "1981-08-04T12:03:03+08:00",
              "utc": "1981-08-04T04:03:03Z",
              "ms": 365745783454.93933
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-08-05",
          "window": {
            "start": {
              "local": "1981-08-05T11:14:58+08:00",
              "utc": "1981-08-05T03:14:58Z",
              "ms": 365829297683.5807
            },
            "end": {
              "local": "1981-08-05T12:02:58+08:00",
              "utc": "1981-08-05T04:02:58Z",
              "ms": 365832177683.5807
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pañcamī runs from 09:37 on Tue 4 Aug to 10:39 on Wed 5 Aug.",
          "fact": "1981-08-04T01:37:25Z → 1981-08-05T02:38:41Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:15–12:03 on the 4th, 11:15–12:03 on the 5th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pañcamī must be present during madhyāhna. It covers 48 of 48 minutes on the 4th and 0 of 48 on the 5th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 2177 s"
        },
        {
          "step": "ruling",
          "text": "Nāga Pañcamī, Harbin, 1981: Tuesday 4 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "naga-panchami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 5 Naga pancami (paraviddha)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-04",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-05",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Nāga Pañcamī 1981 falls on Tuesday 4 August. Pañcamī runs from 09:37 on Tue 4 Aug to 10:39 on Wed 5 Aug and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/naga-panchami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-08-11",
      "festival": "ekadashi",
      "name": "Putradā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 19827,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-08-10T21:09:39+08:00",
          "utc": "1981-08-10T13:09:39Z",
          "ms": 366296979396.62054
        },
        "end": {
          "local": "1981-08-11T22:58:49+08:00",
          "utc": "1981-08-11T14:58:49Z",
          "ms": 366389928715.32263
        },
        "month": {
          "amanta": 4,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-10T21:09:39+08:00",
          "utc": "1981-08-10T13:09:39Z",
          "ms": 366296979396.62054
        },
        "end": {
          "local": "1981-08-11T22:58:49+08:00",
          "utc": "1981-08-11T14:58:49Z",
          "ms": 366389928715.32263
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-08-11",
          "window": {
            "start": {
              "local": "1981-08-11T04:28:03+08:00",
              "utc": "1981-08-10T20:28:03Z",
              "ms": 366323282728.39886
            },
            "end": {
              "local": "1981-08-11T04:28:03+08:00",
              "utc": "1981-08-10T20:28:03Z",
              "ms": 366323282728.39886
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-08-12",
          "window": {
            "start": {
              "local": "1981-08-12T04:29:16+08:00",
              "utc": "1981-08-11T20:29:16Z",
              "ms": 366409755937.69995
            },
            "end": {
              "local": "1981-08-12T04:29:16+08:00",
              "utc": "1981-08-11T20:29:16Z",
              "ms": 366409755937.69995
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 21:10 on Mon 10 Aug to 22:59 on Tue 11 Aug.",
          "fact": "1981-08-10T13:09:39Z → 1981-08-11T14:58:49Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 04:28 on the 11th and 04:29 on the 12th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 11th and is not on the 12th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 19827 s"
        },
        {
          "step": "ruling",
          "text": "Putradā Ekādaśī, Harbin, 1981: Tuesday 11 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Putradā Ekādaśī 1981 falls on Tuesday 11 August. Ekādaśī runs from 21:10 on Mon 10 Aug to 22:59 on Tue 11 Aug and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-08-11",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/damodara-dvadashi",
      "festival": "damodara-dvadashi",
      "name": "Dāmodara Dvādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-12",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 39391,
      "anga": {
        "type": "tithi",
        "index": 11,
        "key": "dvadashi",
        "name": "Dvādaśī",
        "start": {
          "local": "1981-08-11T22:58:49+08:00",
          "utc": "1981-08-11T14:58:49Z",
          "ms": 366389928715.32263
        },
        "end": {
          "local": "1981-08-13T00:17:19+08:00",
          "utc": "1981-08-12T16:17:19Z",
          "ms": 366481039001.4711
        },
        "month": {
          "amanta": 4,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-11T22:58:49+08:00",
          "utc": "1981-08-11T14:58:49Z",
          "ms": 366389928715.32263
        },
        "end": {
          "local": "1981-08-13T00:17:19+08:00",
          "utc": "1981-08-12T16:17:19Z",
          "ms": 366481039001.4711
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-12",
          "window": {
            "start": {
              "local": "1981-08-12T11:14:01+08:00",
              "utc": "1981-08-12T03:14:01Z",
              "ms": 366434040640.55835
            },
            "end": {
              "local": "1981-08-12T12:02:01+08:00",
              "utc": "1981-08-12T04:02:01Z",
              "ms": 366436920640.55835
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-08-13",
          "window": {
            "start": {
              "local": "1981-08-13T11:13:50+08:00",
              "utc": "1981-08-13T03:13:50Z",
              "ms": 366520430186.69574
            },
            "end": {
              "local": "1981-08-13T12:01:50+08:00",
              "utc": "1981-08-13T04:01:50Z",
              "ms": 366523310186.69574
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvādaśī runs from 22:59 on Tue 11 Aug to 00:17 on Thu 13 Aug.",
          "fact": "1981-08-11T14:58:49Z → 1981-08-12T16:17:19Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:14–12:02 on the 12th, 11:14–12:02 on the 13th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvādaśī must be present during madhyāhna. It covers 48 of 48 minutes on the 12th and 0 of 48 on the 13th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 39391 s"
        },
        {
          "step": "ruling",
          "text": "Dāmodara Dvādaśī, Harbin, 1981: Wednesday 12 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "damodara-dvadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 12 Buddha dvadasi, Damodara dvadasi (purvaviddha), Visnu-pavitraropana."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-12",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-12",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Dāmodara Dvādaśī 1981 falls on Wednesday 12 August. Dvādaśī runs from 22:59 on Tue 11 Aug to 00:17 on Thu 13 Aug and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/damodara-dvadashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-08-13",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-13",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 15164,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-08-13T00:17:19+08:00",
          "utc": "1981-08-12T16:17:19Z",
          "ms": 366481039001.4711
        },
        "end": {
          "local": "1981-08-14T01:00:14+08:00",
          "utc": "1981-08-13T17:00:14Z",
          "ms": 366570014091.72876
        },
        "month": {
          "amanta": 4,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-13T00:17:19+08:00",
          "utc": "1981-08-12T16:17:19Z",
          "ms": 366481039001.4711
        },
        "end": {
          "local": "1981-08-14T01:00:14+08:00",
          "utc": "1981-08-13T17:00:14Z",
          "ms": 366570014091.72876
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-08-12",
          "window": {
            "start": {
              "local": "1981-08-12T18:46:45+08:00",
              "utc": "1981-08-12T10:46:45Z",
              "ms": 366461205343.4167
            },
            "end": {
              "local": "1981-08-12T20:04:35+08:00",
              "utc": "1981-08-12T12:04:35Z",
              "ms": 366465875202.8562
            }
          },
          "covered_min": 0,
          "window_min": 78,
          "qualifies": false
        },
        {
          "local_date": "1981-08-13",
          "window": {
            "start": {
              "local": "1981-08-13T18:45:11+08:00",
              "utc": "1981-08-13T10:45:11Z",
              "ms": 366547511084.17834
            },
            "end": {
              "local": "1981-08-13T20:03:23+08:00",
              "utc": "1981-08-13T12:03:23Z",
              "ms": 366552203308.2657
            }
          },
          "covered_min": 78,
          "window_min": 78,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 00:17 on Thu 13 Aug to 01:00 on Fri 14 Aug.",
          "fact": "1981-08-12T16:17:19Z → 1981-08-13T17:00:14Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:47–20:05 on the 12th, 18:45–20:03 on the 13th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 78 minutes on the 12th and 78 of 78 on the 13th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 15164 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Thursday 13 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-13",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-13",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Thursday 13 August. Trayodaśī runs from 00:17 on Thu 13 Aug to 01:00 on Fri 14 Aug and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-08-13",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/raksha-bandhana",
      "festival": "raksha-bandhana",
      "name": "Rakṣā Bandhana",
      "everyday": "Rakhi",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-15",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 14253,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-08-15T01:06:09+08:00",
          "utc": "1981-08-14T17:06:09Z",
          "ms": 366656769467.0725
        },
        "end": {
          "local": "1981-08-16T00:36:37+08:00",
          "utc": "1981-08-15T16:36:37Z",
          "ms": 366741397298.87384
        },
        "month": {
          "amanta": 4,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "second-half",
        "start": {
          "local": "1981-08-15T12:55:38+08:00",
          "utc": "1981-08-15T04:55:38Z",
          "ms": 366699337931.54834
        },
        "end": {
          "local": "1981-08-16T00:36:37+08:00",
          "utc": "1981-08-15T16:36:37Z",
          "ms": 366741397298.87384
        }
      },
      "kaala": "day",
      "days": [
        {
          "local_date": "1981-08-15",
          "window": {
            "start": {
              "local": "1981-08-15T04:32:56+08:00",
              "utc": "1981-08-14T20:32:56Z",
              "ms": 366669176348.74194
            },
            "end": {
              "local": "1981-08-16T04:34:10+08:00",
              "utc": "1981-08-15T20:34:10Z",
              "ms": 366755650027.43286
            }
          },
          "covered_min": 701,
          "window_min": 1441,
          "qualifies": true
        },
        {
          "local_date": "1981-08-16",
          "window": {
            "start": {
              "local": "1981-08-16T04:34:10+08:00",
              "utc": "1981-08-15T20:34:10Z",
              "ms": 366755650027.43286
            },
            "end": {
              "local": "1981-08-17T04:35:24+08:00",
              "utc": "1981-08-16T20:35:24Z",
              "ms": 366842123789.63116
            }
          },
          "covered_min": 0,
          "window_min": 1441,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 01:06 on Sat 15 Aug to 00:37 on Sun 16 Aug. Its second half begins at 12:56 on Sat 15 Aug.",
          "fact": "1981-08-14T17:06:09Z → 1981-08-15T16:36:37Z · second half from 1981-08-15T04:55:38Z"
        },
        {
          "step": "kaala",
          "text": "The day runs from sunrise to the next sunrise: from 04:33 on the 15th, and from 04:34 on the 16th.",
          "fact": "day: sunrise-to-sunrise · sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "The second half of Pūrṇimā must be present during the day. It covers 701 of 1441 minutes on the 15th and 0 of 1441 on the 16th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one day qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 14253 s"
        },
        {
          "step": "ruling",
          "text": "Rakṣā Bandhana, Harbin, 1981: Saturday 15 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "raksha-bandhana",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Rakhi purnima, Naroli purnima (Cocoanut day), Raksa Bandhana (in the second half of purnima), Rsi tarpana (madhyahna vyapini), Hayagriva utpatti, Jhulanayatra samapana"
          }
        ],
        "kaala": "day",
        "priority": "unstated",
        "when_absent": "unstated",
        "half": "second"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-15",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-15",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Rakṣā Bandhana (Rakhi) 1981 falls on Saturday 15 August. The second half of Pūrṇimā runs from 12:56 on Sat 15 Aug to 00:37 on Sun 16 Aug and lies within that day, sunrise to sunrise.",
      "cite": "https://ahargana.org/harbin/festivals/1981/raksha-bandhana",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/rishi-tarpana",
      "festival": "rishi-tarpana",
      "name": "Ṛṣi Tarpaṇa",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-15",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 36438,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-08-15T01:06:09+08:00",
          "utc": "1981-08-14T17:06:09Z",
          "ms": 366656769467.0725
        },
        "end": {
          "local": "1981-08-16T00:36:37+08:00",
          "utc": "1981-08-15T16:36:37Z",
          "ms": 366741397298.87384
        },
        "month": {
          "amanta": 4,
          "purnimanta": 4,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Śrāvaṇa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-15T01:06:09+08:00",
          "utc": "1981-08-14T17:06:09Z",
          "ms": 366656769467.0725
        },
        "end": {
          "local": "1981-08-16T00:36:37+08:00",
          "utc": "1981-08-15T16:36:37Z",
          "ms": 366741397298.87384
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-15",
          "window": {
            "start": {
              "local": "1981-08-15T11:13:28+08:00",
              "utc": "1981-08-15T03:13:28Z",
              "ms": 366693207642.1771
            },
            "end": {
              "local": "1981-08-15T12:01:28+08:00",
              "utc": "1981-08-15T04:01:28Z",
              "ms": 366696087642.1771
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-08-16",
          "window": {
            "start": {
              "local": "1981-08-16T11:13:16+08:00",
              "utc": "1981-08-16T03:13:16Z",
              "ms": 366779595575.97925
            },
            "end": {
              "local": "1981-08-16T12:01:16+08:00",
              "utc": "1981-08-16T04:01:16Z",
              "ms": 366782475575.97925
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 01:06 on Sat 15 Aug to 00:37 on Sun 16 Aug.",
          "fact": "1981-08-14T17:06:09Z → 1981-08-15T16:36:37Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:13–12:01 on the 15th, 11:13–12:01 on the 16th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during madhyāhna. It covers 48 of 48 minutes on the 15th and 0 of 48 on the 16th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 36438 s"
        },
        {
          "step": "ruling",
          "text": "Ṛṣi Tarpaṇa, Harbin, 1981: Saturday 15 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "rishi-tarpana",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Rakhi purnima, Naroli purnima (Cocoanut day), Raksa Bandhana (in the second half of purnima), Rsi tarpana (madhyahna vyapini), Hayagriva utpatti, Jhulanayatra samapana"
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-15",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-15",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Ṛṣi Tarpaṇa 1981 falls on Saturday 15 August. Pūrṇimā runs from 01:06 on Sat 15 Aug to 00:37 on Sun 16 Aug and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/rishi-tarpana",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ashunya-shayana-vrata",
      "festival": "ashunya-shayana-vrata",
      "name": "Aśūnya Śayana Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-17",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 8411,
      "anga": {
        "type": "tithi",
        "index": 16,
        "key": "dvitiya",
        "name": "Dvitīyā",
        "start": {
          "local": "1981-08-16T23:35:19+08:00",
          "utc": "1981-08-16T15:35:19Z",
          "ms": 366824119214.3267
        },
        "end": {
          "local": "1981-08-17T22:07:19+08:00",
          "utc": "1981-08-17T14:07:19Z",
          "ms": 366905238745.8564
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-16T23:35:19+08:00",
          "utc": "1981-08-16T15:35:19Z",
          "ms": 366824119214.3267
        },
        "end": {
          "local": "1981-08-17T22:07:19+08:00",
          "utc": "1981-08-17T14:07:19Z",
          "ms": 366905238745.8564
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-08-16",
          "window": {
            "start": {
              "local": "1981-08-16T19:16:02+08:00",
              "utc": "1981-08-16T11:16:02Z",
              "ms": 366808562474.6862
            },
            "end": {
              "local": "1981-08-16T19:16:02+08:00",
              "utc": "1981-08-16T11:16:02Z",
              "ms": 366808562474.6862
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-08-17",
          "window": {
            "start": {
              "local": "1981-08-17T19:47:08+08:00",
              "utc": "1981-08-17T11:47:08Z",
              "ms": 366896827736.6514
            },
            "end": {
              "local": "1981-08-17T19:47:08+08:00",
              "utc": "1981-08-17T11:47:08Z",
              "ms": 366896827736.6514
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvitīyā runs from 23:35 on Sun 16 Aug to 22:07 on Mon 17 Aug.",
          "fact": "1981-08-16T15:35:19Z → 1981-08-17T14:07:19Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 19:16 on the 16th and 19:47 on the 17th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Dvitīyā must be current at moonrise. It is not on the 16th and is on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 8411 s"
        },
        {
          "step": "ruling",
          "text": "Aśūnya Śayana Vrata, Harbin, 1981: Monday 17 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ashunya-shayana-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 2 Asunyasayana vrata (Dvitiya current at moonrise; if occurs on two successive days, it is to be observed on the second day)."
          }
        ],
        "kaala": "moonrise",
        "priority": "paraviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-17",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-17",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Aśūnya Śayana Vrata 1981 falls on Monday 17 August. Dvitīyā runs from 23:35 on Sun 16 Aug to 22:07 on Mon 17 Aug and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ashunya-shayana-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/kajjali-tritiya",
      "festival": "kajjali-tritiya",
      "name": "Kajjalī Tṛtīyā",
      "everyday": "Kajari Teej",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-18",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 29850,
      "anga": {
        "type": "tithi",
        "index": 17,
        "key": "tritiya",
        "name": "Tṛtīyā",
        "start": {
          "local": "1981-08-17T22:07:19+08:00",
          "utc": "1981-08-17T14:07:19Z",
          "ms": 366905238745.8564
        },
        "end": {
          "local": "1981-08-18T20:18:20+08:00",
          "utc": "1981-08-18T12:18:20Z",
          "ms": 366985099831.8458
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-17T22:07:19+08:00",
          "utc": "1981-08-17T14:07:19Z",
          "ms": 366905238745.8564
        },
        "end": {
          "local": "1981-08-18T20:18:20+08:00",
          "utc": "1981-08-18T12:18:20Z",
          "ms": 366985099831.8458
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-17",
          "window": {
            "start": {
              "local": "1981-08-17T11:13:03+08:00",
              "utc": "1981-08-17T03:13:03Z",
              "ms": 366865982998.425
            },
            "end": {
              "local": "1981-08-17T12:01:03+08:00",
              "utc": "1981-08-17T04:01:03Z",
              "ms": 366868862998.425
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-08-18",
          "window": {
            "start": {
              "local": "1981-08-18T11:12:50+08:00",
              "utc": "1981-08-18T03:12:50Z",
              "ms": 366952369923.9468
            },
            "end": {
              "local": "1981-08-18T12:00:50+08:00",
              "utc": "1981-08-18T04:00:50Z",
              "ms": 366955249923.9468
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Tṛtīyā runs from 22:07 on Mon 17 Aug to 20:18 on Tue 18 Aug.",
          "fact": "1981-08-17T14:07:19Z → 1981-08-18T12:18:20Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:13–12:01 on the 17th, 11:13–12:01 on the 18th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Tṛtīyā must be present during madhyāhna. It covers 0 of 48 minutes on the 17th and 48 of 48 on the 18th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 29850 s"
        },
        {
          "step": "ruling",
          "text": "Kajjalī Tṛtīyā, Harbin, 1981: Tuesday 18 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "kajjali-tritiya",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 3 Kajjali trtiya, (paraviddha), Angaveta trtiya (Orissa)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-18",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-18",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kajjalī Tṛtīyā (Kajari Teej) 1981 falls on Tuesday 18 August. Tṛtīyā runs from 22:07 on Mon 17 Aug to 20:18 on Tue 18 Aug and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/kajjali-tritiya",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-08-18",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-18",
      "confidence": "boundary",
      "boundary_reasons": [
        "margin",
        "absent-unstated"
      ],
      "boundary_margin_s": 131,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-08-18T20:18:20+08:00",
          "utc": "1981-08-18T12:18:20Z",
          "ms": 366985099831.8458
        },
        "end": {
          "local": "1981-08-19T18:14:14+08:00",
          "utc": "1981-08-19T10:14:14Z",
          "ms": 367064053604.26855
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-18T20:18:20+08:00",
          "utc": "1981-08-18T12:18:20Z",
          "ms": 366985099831.8458
        },
        "end": {
          "local": "1981-08-19T18:14:14+08:00",
          "utc": "1981-08-19T10:14:14Z",
          "ms": 367064053604.26855
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-08-18",
          "window": {
            "start": {
              "local": "1981-08-18T20:16:09+08:00",
              "utc": "1981-08-18T12:16:09Z",
              "ms": 366984969239.4207
            },
            "end": {
              "local": "1981-08-18T20:16:09+08:00",
              "utc": "1981-08-18T12:16:09Z",
              "ms": 366984969239.4207
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-08-19",
          "window": {
            "start": {
              "local": "1981-08-19T20:44:29+08:00",
              "utc": "1981-08-19T12:44:29Z",
              "ms": 367073068645.3291
            },
            "end": {
              "local": "1981-08-19T20:44:29+08:00",
              "utc": "1981-08-19T12:44:29Z",
              "ms": 367073068645.3291
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "tithi-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 20:18 on Tue 18 Aug to 18:14 on Wed 19 Aug.",
          "fact": "1981-08-18T12:18:20Z → 1981-08-19T10:14:14Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 20:16 on the 18th and 20:44 on the 19th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is not on the 18th and is not on the 19th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Neither moonrise qualifies. The day the tithi falls on is taken.",
          "fact": "priority: unstated → tithi-day · margin 131 s < 300 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Tuesday 18 August.",
          "fact": "confidence: boundary (margin, absent-unstated)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-18",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-18",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Tuesday 18 August. Caturthī runs from 20:18 on Tue 18 Aug to 18:14 on Wed 19 Aug, and is current at moonrise on neither day. It is 2 min 11 s from a threshold: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-08-18",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/bahula-chaturthi",
      "festival": "bahula-chaturthi",
      "name": "Bahulā Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-19",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1268,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-08-18T20:18:20+08:00",
          "utc": "1981-08-18T12:18:20Z",
          "ms": 366985099831.8458
        },
        "end": {
          "local": "1981-08-19T18:14:14+08:00",
          "utc": "1981-08-19T10:14:14Z",
          "ms": 367064053604.26855
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-18T20:18:20+08:00",
          "utc": "1981-08-18T12:18:20Z",
          "ms": 366985099831.8458
        },
        "end": {
          "local": "1981-08-19T18:14:14+08:00",
          "utc": "1981-08-19T10:14:14Z",
          "ms": 367064053604.26855
        }
      },
      "kaala": "sayahna",
      "days": [
        {
          "local_date": "1981-08-18",
          "window": {
            "start": {
              "local": "1981-08-18T15:48:57+08:00",
              "utc": "1981-08-18T07:48:57Z",
              "ms": 366968937302.68835
            },
            "end": {
              "local": "1981-08-18T18:37:02+08:00",
              "utc": "1981-08-18T10:37:02Z",
              "ms": 366979022221.8494
            }
          },
          "covered_min": 0,
          "window_min": 168,
          "qualifies": false
        },
        {
          "local_date": "1981-08-19",
          "window": {
            "start": {
              "local": "1981-08-19T15:47:51+08:00",
              "utc": "1981-08-19T07:47:51Z",
              "ms": 367055271270.59814
            },
            "end": {
              "local": "1981-08-19T18:35:21+08:00",
              "utc": "1981-08-19T10:35:21Z",
              "ms": 367065321206.0154
            }
          },
          "covered_min": 146,
          "window_min": 167,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 20:18 on Tue 18 Aug to 18:14 on Wed 19 Aug.",
          "fact": "1981-08-18T12:18:20Z → 1981-08-19T10:14:14Z"
        },
        {
          "step": "kaala",
          "text": "Sāyāhna is last 3 of 15 day muhūrtas: 15:49–18:37 on the 18th, 15:48–18:35 on the 19th.",
          "fact": "sayahna: day-muhurta-13-15 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during sāyāhna. It covers 0 of 168 minutes on the 18th and 146 of 167 on the 19th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one late afternoon qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 1268 s"
        },
        {
          "step": "ruling",
          "text": "Bahulā Caturthī, Harbin, 1981: Wednesday 19 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "bahula-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 4 Bahula caturthi (Madhyadesa) (Sayahnavyapini: if occurs on two successive days, it is to be observed on the 1st day)."
          }
        ],
        "kaala": "sayahna",
        "priority": "purvaviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-19",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-19",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Bahulā Caturthī 1981 falls on Wednesday 19 August. Caturthī runs from 20:18 on Tue 18 Aug to 18:14 on Wed 19 Aug and covers 146 of 167 minutes of sāyāhna that late afternoon.",
      "cite": "https://ahargana.org/harbin/festivals/1981/bahula-chaturthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/hala-shashthi",
      "festival": "hala-shashthi",
      "name": "Hala Ṣaṣṭhī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-21",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 6131,
      "anga": {
        "type": "tithi",
        "index": 20,
        "key": "shashthi",
        "name": "Ṣaṣṭhī",
        "start": {
          "local": "1981-08-20T16:00:34+08:00",
          "utc": "1981-08-20T08:00:34Z",
          "ms": 367142433638.81696
        },
        "end": {
          "local": "1981-08-21T13:42:19+08:00",
          "utc": "1981-08-21T05:42:19Z",
          "ms": 367220539318.8948
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-20T16:00:34+08:00",
          "utc": "1981-08-20T08:00:34Z",
          "ms": 367142433638.81696
        },
        "end": {
          "local": "1981-08-21T13:42:19+08:00",
          "utc": "1981-08-21T05:42:19Z",
          "ms": 367220539318.8948
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-20",
          "window": {
            "start": {
              "local": "1981-08-20T11:12:22+08:00",
              "utc": "1981-08-20T03:12:22Z",
              "ms": 367125142344.11694
            },
            "end": {
              "local": "1981-08-20T12:00:22+08:00",
              "utc": "1981-08-20T04:00:22Z",
              "ms": 367128022344.11694
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-08-21",
          "window": {
            "start": {
              "local": "1981-08-21T11:12:08+08:00",
              "utc": "1981-08-21T03:12:08Z",
              "ms": 367211527868.8581
            },
            "end": {
              "local": "1981-08-21T12:00:08+08:00",
              "utc": "1981-08-21T04:00:08Z",
              "ms": 367214407868.8581
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ṣaṣṭhī runs from 16:01 on Thu 20 Aug to 13:42 on Fri 21 Aug.",
          "fact": "1981-08-20T08:00:34Z → 1981-08-21T05:42:19Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:12–12:00 on the 20th, 11:12–12:00 on the 21st.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ṣaṣṭhī must be present during madhyāhna. It covers 0 of 48 minutes on the 20th and 48 of 48 on the 21st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 6131 s"
        },
        {
          "step": "ruling",
          "text": "Hala Ṣaṣṭhī, Harbin, 1981: Friday 21 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "hala-shashthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 6 Hala sasthi (paraviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-21",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-21",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Hala Ṣaṣṭhī 1981 falls on Friday 21 August. Ṣaṣṭhī runs from 16:01 on Thu 20 Aug to 13:42 on Fri 21 Aug and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/hala-shashthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/janmashtami",
      "festival": "janmashtami",
      "name": "Janmāṣṭamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-22",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 32880,
      "anga": {
        "type": "tithi",
        "index": 22,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-08-22T11:23:47+08:00",
          "utc": "1981-08-22T03:23:47Z",
          "ms": 367298627150.3977
        },
        "end": {
          "local": "1981-08-23T09:08:30+08:00",
          "utc": "1981-08-23T01:08:30Z",
          "ms": 367376910033.1884
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-22T11:23:47+08:00",
          "utc": "1981-08-22T03:23:47Z",
          "ms": 367298627150.3977
        },
        "end": {
          "local": "1981-08-23T09:08:30+08:00",
          "utc": "1981-08-23T01:08:30Z",
          "ms": 367376910033.1884
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-08-21",
          "window": {
            "start": {
              "local": "1981-08-21T23:12:45+08:00",
              "utc": "1981-08-21T15:12:45Z",
              "ms": 367254764900.161
            },
            "end": {
              "local": "1981-08-22T00:00:45+08:00",
              "utc": "1981-08-21T16:00:45Z",
              "ms": 367257644900.161
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-08-22",
          "window": {
            "start": {
              "local": "1981-08-22T23:12:30+08:00",
              "utc": "1981-08-22T15:12:30Z",
              "ms": 367341150007.3286
            },
            "end": {
              "local": "1981-08-23T00:00:30+08:00",
              "utc": "1981-08-22T16:00:30Z",
              "ms": 367344030007.3286
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 11:24 on Sat 22 Aug to 09:09 on Sun 23 Aug.",
          "fact": "1981-08-22T03:23:47Z → 1981-08-23T01:08:30Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:13–00:01 on the 21st, 23:13–00:01 on the 22nd.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be present during niśītha. It covers 0 of 48 minutes on the 21st and 48 of 48 on the 22nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 32880 s"
        },
        {
          "step": "ruling",
          "text": "Janmāṣṭamī, Harbin, 1981: Saturday 22 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "janmashtami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 8 Janmastami (madhyaratra-vyapini), if midnight is covered on two days, or not on any day, it is to be observed on the 2nd day; special when combined with naksatra 'Rohini' at midnight, more so when on Monday or Wednesday. If the combination occurs before midnight and 'Rohini' extends up to midnight, it is to be observed on that day. Gokulastami."
          }
        ],
        "not_evaluated": "The clauses on Rohiṇī nakṣatra, the Vaiṣṇava observance on the day after saptamī, and the Assam and South India reckoning in the solar month belong to other readings and are not applied.",
        "kaala": "nishita",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-22",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-22",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Janmāṣṭamī 1981 falls on Saturday 22 August. Aṣṭamī runs from 11:24 on Sat 22 Aug to 09:09 on Sun 23 Aug and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/janmashtami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shitala-saptami",
      "festival": "shitala-saptami",
      "name": "Śītalā Saptamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-22",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 714,
      "anga": {
        "type": "tithi",
        "index": 21,
        "key": "saptami",
        "name": "Saptamī",
        "start": {
          "local": "1981-08-21T13:42:19+08:00",
          "utc": "1981-08-21T05:42:19Z",
          "ms": 367220539318.8948
        },
        "end": {
          "local": "1981-08-22T11:23:47+08:00",
          "utc": "1981-08-22T03:23:47Z",
          "ms": 367298627150.3977
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-21T13:42:19+08:00",
          "utc": "1981-08-21T05:42:19Z",
          "ms": 367220539318.8948
        },
        "end": {
          "local": "1981-08-22T11:23:47+08:00",
          "utc": "1981-08-22T03:23:47Z",
          "ms": 367298627150.3977
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-21",
          "window": {
            "start": {
              "local": "1981-08-21T11:12:08+08:00",
              "utc": "1981-08-21T03:12:08Z",
              "ms": 367211527868.8581
            },
            "end": {
              "local": "1981-08-21T12:00:08+08:00",
              "utc": "1981-08-21T04:00:08Z",
              "ms": 367214407868.8581
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-08-22",
          "window": {
            "start": {
              "local": "1981-08-22T11:11:53+08:00",
              "utc": "1981-08-22T03:11:53Z",
              "ms": 367297912956.2336
            },
            "end": {
              "local": "1981-08-22T11:59:53+08:00",
              "utc": "1981-08-22T03:59:53Z",
              "ms": 367300792956.2336
            }
          },
          "covered_min": 12,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Saptamī runs from 13:42 on Fri 21 Aug to 11:24 on Sat 22 Aug.",
          "fact": "1981-08-21T05:42:19Z → 1981-08-22T03:23:47Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:12–12:00 on the 21st, 11:12–12:00 on the 22nd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Saptamī must be present during madhyāhna. It covers 0 of 48 minutes on the 21st and 12 of 48 on the 22nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 714 s"
        },
        {
          "step": "ruling",
          "text": "Śītalā Saptamī, Harbin, 1981: Saturday 22 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shitala-saptami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 7 Sitala saptami (purvaviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-22",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-22",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śītalā Saptamī 1981 falls on Saturday 22 August. Saptamī runs from 13:42 on Fri 21 Aug to 11:24 on Sat 22 Aug and covers 12 of 48 minutes of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shitala-saptami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-08-25",
      "festival": "ekadashi",
      "name": "Ajā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-25",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 826,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-08-25T04:59:02+08:00",
          "utc": "1981-08-24T20:59:02Z",
          "ms": 367534742357.5245
        },
        "end": {
          "local": "1981-08-26T03:09:51+08:00",
          "utc": "1981-08-25T19:09:51Z",
          "ms": 367614591052.00726
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-25T04:59:02+08:00",
          "utc": "1981-08-24T20:59:02Z",
          "ms": 367534742357.5245
        },
        "end": {
          "local": "1981-08-26T03:09:51+08:00",
          "utc": "1981-08-25T19:09:51Z",
          "ms": 367614591052.00726
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-08-25",
          "window": {
            "start": {
              "local": "1981-08-25T04:45:16+08:00",
              "utc": "1981-08-24T20:45:16Z",
              "ms": 367533915963.4536
            },
            "end": {
              "local": "1981-08-25T04:45:16+08:00",
              "utc": "1981-08-24T20:45:16Z",
              "ms": 367533915963.4536
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-08-26",
          "window": {
            "start": {
              "local": "1981-08-26T04:46:30+08:00",
              "utc": "1981-08-25T20:46:30Z",
              "ms": 367620390135.24176
            },
            "end": {
              "local": "1981-08-26T04:46:30+08:00",
              "utc": "1981-08-25T20:46:30Z",
              "ms": 367620390135.24176
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "tithi-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 04:59 on Tue 25 Aug to 03:10 on Wed 26 Aug.",
          "fact": "1981-08-24T20:59:02Z → 1981-08-25T19:09:51Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 04:45 on the 25th and 04:47 on the 26th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 25th and is not on the 26th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Neither sunrise qualifies. The day the tithi falls on is taken.",
          "fact": "priority: paraviddha → tithi-day · margin 826 s"
        },
        {
          "step": "ruling",
          "text": "Ajā Ekādaśī, Harbin, 1981: Tuesday 25 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-25",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-25",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Ajā Ekādaśī 1981 falls on Tuesday 25 August. Ekādaśī runs from 04:59 on Tue 25 Aug to 03:10 on Wed 26 Aug, and is current at sunrise on neither day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-08-25",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-08-27",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-27",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 16251,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-08-27T01:34:27+08:00",
          "utc": "1981-08-26T17:34:27Z",
          "ms": 367695267497.39154
        },
        "end": {
          "local": "1981-08-28T00:15:53+08:00",
          "utc": "1981-08-27T16:15:53Z",
          "ms": 367776952548.84796
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-27T01:34:27+08:00",
          "utc": "1981-08-26T17:34:27Z",
          "ms": 367695267497.39154
        },
        "end": {
          "local": "1981-08-28T00:15:53+08:00",
          "utc": "1981-08-27T16:15:53Z",
          "ms": 367776952548.84796
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-08-26",
          "window": {
            "start": {
              "local": "1981-08-26T18:23:08+08:00",
              "utc": "1981-08-26T10:23:08Z",
              "ms": 367669388259.7915
            },
            "end": {
              "local": "1981-08-26T19:46:25+08:00",
              "utc": "1981-08-26T11:46:25Z",
              "ms": 367674385066.8395
            }
          },
          "covered_min": 0,
          "window_min": 83,
          "qualifies": false
        },
        {
          "local_date": "1981-08-27",
          "window": {
            "start": {
              "local": "1981-08-27T18:21:20+08:00",
              "utc": "1981-08-27T10:21:20Z",
              "ms": 367755680268.56555
            },
            "end": {
              "local": "1981-08-27T19:45:01+08:00",
              "utc": "1981-08-27T11:45:01Z",
              "ms": 367760701364.37524
            }
          },
          "covered_min": 84,
          "window_min": 84,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 01:34 on Thu 27 Aug to 00:16 on Fri 28 Aug.",
          "fact": "1981-08-26T17:34:27Z → 1981-08-27T16:15:53Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:23–19:46 on the 26th, 18:21–19:45 on the 27th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 83 minutes on the 26th and 84 of 84 on the 27th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 16251 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Thursday 27 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-27",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-27",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Thursday 27 August. Trayodaśī runs from 01:34 on Thu 27 Aug to 00:16 on Fri 28 Aug and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-08-27",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/aghora-chaturdashi",
      "festival": "aghora-chaturdashi",
      "name": "Aghora Caturdaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-28",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 12838,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-08-28T00:15:53+08:00",
          "utc": "1981-08-27T16:15:53Z",
          "ms": 367776952548.84796
        },
        "end": {
          "local": "1981-08-28T23:17:35+08:00",
          "utc": "1981-08-28T15:17:35Z",
          "ms": 367859855092.6528
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-28T00:15:53+08:00",
          "utc": "1981-08-27T16:15:53Z",
          "ms": 367776952548.84796
        },
        "end": {
          "local": "1981-08-28T23:17:35+08:00",
          "utc": "1981-08-28T15:17:35Z",
          "ms": 367859855092.6528
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-08-27",
          "window": {
            "start": {
              "local": "1981-08-27T18:21:20+08:00",
              "utc": "1981-08-27T10:21:20Z",
              "ms": 367755680268.56555
            },
            "end": {
              "local": "1981-08-27T19:45:01+08:00",
              "utc": "1981-08-27T11:45:01Z",
              "ms": 367760701364.37524
            }
          },
          "covered_min": 0,
          "window_min": 84,
          "qualifies": false
        },
        {
          "local_date": "1981-08-28",
          "window": {
            "start": {
              "local": "1981-08-28T18:19:32+08:00",
              "utc": "1981-08-28T10:19:32Z",
              "ms": 367841971550.71375
            },
            "end": {
              "local": "1981-08-28T19:43:37+08:00",
              "utc": "1981-08-28T11:43:37Z",
              "ms": 367847017030.73413
            }
          },
          "covered_min": 84,
          "window_min": 84,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 00:16 on Fri 28 Aug to 23:18 on Fri 28 Aug.",
          "fact": "1981-08-27T16:15:53Z → 1981-08-28T15:17:35Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 18:21–19:45 on the 27th, 18:20–19:44 on the 28th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during pradoṣa. It covers 0 of 84 minutes on the 27th and 84 of 84 on the 28th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 12838 s"
        },
        {
          "step": "ruling",
          "text": "Aghora Caturdaśī, Harbin, 1981: Friday 28 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "aghora-chaturdashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 14 Aghora caturdasi (pradosa vyapini)."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-28",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-28",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Aghora Caturdaśī 1981 falls on Friday 28 August. Caturdaśī runs from 00:16 on Fri 28 Aug to 23:18 on Fri 28 Aug and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/aghora-chaturdashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-08-28",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-28",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 403,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-08-28T00:15:53+08:00",
          "utc": "1981-08-27T16:15:53Z",
          "ms": 367776952548.84796
        },
        "end": {
          "local": "1981-08-28T23:17:35+08:00",
          "utc": "1981-08-28T15:17:35Z",
          "ms": 367859855092.6528
        },
        "month": {
          "amanta": 4,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Śrāvaṇa",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-28T00:15:53+08:00",
          "utc": "1981-08-27T16:15:53Z",
          "ms": 367776952548.84796
        },
        "end": {
          "local": "1981-08-28T23:17:35+08:00",
          "utc": "1981-08-28T15:17:35Z",
          "ms": 367859855092.6528
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-08-27",
          "window": {
            "start": {
              "local": "1981-08-27T23:11:09+08:00",
              "utc": "1981-08-27T15:11:09Z",
              "ms": 367773069377.8518
            },
            "end": {
              "local": "1981-08-27T23:59:09+08:00",
              "utc": "1981-08-27T15:59:09Z",
              "ms": 367775949377.8518
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-08-28",
          "window": {
            "start": {
              "local": "1981-08-28T23:10:52+08:00",
              "utc": "1981-08-28T15:10:52Z",
              "ms": 367859452100.79016
            },
            "end": {
              "local": "1981-08-28T23:58:52+08:00",
              "utc": "1981-08-28T15:58:52Z",
              "ms": 367862332100.79016
            }
          },
          "covered_min": 7,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 00:16 on Fri 28 Aug to 23:18 on Fri 28 Aug.",
          "fact": "1981-08-27T16:15:53Z → 1981-08-28T15:17:35Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:11–23:59 on the 27th, 23:11–23:59 on the 28th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 0 of 48 minutes on the 27th and 7 of 48 on the 28th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 403 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Friday 28 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-28",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-28",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Friday 28 August. Caturdaśī runs from 00:16 on Fri 28 Aug to 23:18 on Fri 28 Aug and covers 7 of 48 minutes of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-08-28",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/rudra-vrata",
      "festival": "rudra-vrata",
      "name": "Rudra Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-08-30",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 38371,
      "anga": {
        "type": "tithi",
        "index": 0,
        "key": "pratipada",
        "name": "Pratipadā",
        "start": {
          "local": "1981-08-29T22:43:25+08:00",
          "utc": "1981-08-29T14:43:25Z",
          "ms": 367944204680.5984
        },
        "end": {
          "local": "1981-08-30T22:37:10+08:00",
          "utc": "1981-08-30T14:37:10Z",
          "ms": 368030230044.1023
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-29T22:43:25+08:00",
          "utc": "1981-08-29T14:43:25Z",
          "ms": 367944204680.5984
        },
        "end": {
          "local": "1981-08-30T22:37:10+08:00",
          "utc": "1981-08-30T14:37:10Z",
          "ms": 368030230044.1023
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-29",
          "window": {
            "start": {
              "local": "1981-08-29T11:09:57+08:00",
              "utc": "1981-08-29T03:09:57Z",
              "ms": 367902597393.3436
            },
            "end": {
              "local": "1981-08-29T11:57:57+08:00",
              "utc": "1981-08-29T03:57:57Z",
              "ms": 367905477393.3436
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-08-30",
          "window": {
            "start": {
              "local": "1981-08-30T11:09:39+08:00",
              "utc": "1981-08-30T03:09:39Z",
              "ms": 367988979425.1102
            },
            "end": {
              "local": "1981-08-30T11:57:39+08:00",
              "utc": "1981-08-30T03:57:39Z",
              "ms": 367991859425.1102
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pratipadā runs from 22:43 on Sat 29 Aug to 22:37 on Sun 30 Aug.",
          "fact": "1981-08-29T14:43:25Z → 1981-08-30T14:37:10Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:10–11:58 on the 29th, 11:10–11:58 on the 30th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pratipadā must be present during madhyāhna. It covers 0 of 48 minutes on the 29th and 48 of 48 on the 30th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 38371 s"
        },
        {
          "step": "ruling",
          "text": "Rudra Vrata, Harbin, 1981: Sunday 30 August.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "rudra-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 1 Rudra vrata (purvaviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-08-30",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-08-30",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Rudra Vrata 1981 falls on Sunday 30 August. Pratipadā runs from 22:43 on Sat 29 Aug to 22:37 on Sun 30 Aug and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/rudra-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/haritalika-vrata",
      "festival": "haritalika-vrata",
      "name": "Haritālikā Vrata",
      "everyday": "Hartalika Teej",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-01",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 39881,
      "anga": {
        "type": "tithi",
        "index": 2,
        "key": "tritiya",
        "name": "Tṛtīyā",
        "start": {
          "local": "1981-08-31T23:02:03+08:00",
          "utc": "1981-08-31T15:02:03Z",
          "ms": 368118122533.92944
        },
        "end": {
          "local": "1981-09-01T23:59:46+08:00",
          "utc": "1981-09-01T15:59:46Z",
          "ms": 368207985891.4933
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-08-31T23:02:03+08:00",
          "utc": "1981-08-31T15:02:03Z",
          "ms": 368118122533.92944
        },
        "end": {
          "local": "1981-09-01T23:59:46+08:00",
          "utc": "1981-09-01T15:59:46Z",
          "ms": 368207985891.4933
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-08-31",
          "window": {
            "start": {
              "local": "1981-08-31T11:09:21+08:00",
              "utc": "1981-08-31T03:09:21Z",
              "ms": 368075361126.0945
            },
            "end": {
              "local": "1981-08-31T11:57:21+08:00",
              "utc": "1981-08-31T03:57:21Z",
              "ms": 368078241126.0945
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-09-01",
          "window": {
            "start": {
              "local": "1981-09-01T11:09:03+08:00",
              "utc": "1981-09-01T03:09:03Z",
              "ms": 368161742509.037
            },
            "end": {
              "local": "1981-09-01T11:57:03+08:00",
              "utc": "1981-09-01T03:57:03Z",
              "ms": 368164622509.037
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Tṛtīyā runs from 23:02 on Mon 31 Aug to 00:00 on Tue 1 Sep.",
          "fact": "1981-08-31T15:02:03Z → 1981-09-01T15:59:46Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:09–11:57 on the 31st, 11:09–11:57 on the 1st.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Tṛtīyā must be present during madhyāhna. It covers 0 of 48 minutes on the 31st and 48 of 48 on the 1st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 39881 s"
        },
        {
          "step": "ruling",
          "text": "Haritālikā Vrata, Harbin, 1981: Tuesday 1 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "haritalika-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 3 Haritalika vrata (paraviddha), Gauri vrata (Orissa), Gauri (Mysore)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-01",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-01",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Haritālikā Vrata (Hartalika Teej) 1981 falls on Tuesday 1 September. Tṛtīyā runs from 23:02 on Mon 31 Aug to 00:00 on Tue 1 Sep and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/haritalika-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ganesha-chaturthi",
      "festival": "ganesha-chaturthi",
      "name": "Gaṇeśa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-02",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 34726,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-09-01T23:59:46+08:00",
          "utc": "1981-09-01T15:59:46Z",
          "ms": 368207985891.4933
        },
        "end": {
          "local": "1981-09-03T01:29:38+08:00",
          "utc": "1981-09-02T17:29:38Z",
          "ms": 368299778069.4927
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-01T23:59:46+08:00",
          "utc": "1981-09-01T15:59:46Z",
          "ms": 368207985891.4933
        },
        "end": {
          "local": "1981-09-03T01:29:38+08:00",
          "utc": "1981-09-02T17:29:38Z",
          "ms": 368299778069.4927
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-09-02",
          "window": {
            "start": {
              "local": "1981-09-02T11:08:44+08:00",
              "utc": "1981-09-02T03:08:44Z",
              "ms": 368248123587.6625
            },
            "end": {
              "local": "1981-09-02T11:56:44+08:00",
              "utc": "1981-09-02T03:56:44Z",
              "ms": 368251003587.6625
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-09-03",
          "window": {
            "start": {
              "local": "1981-09-03T11:08:24+08:00",
              "utc": "1981-09-03T03:08:24Z",
              "ms": 368334504376.08887
            },
            "end": {
              "local": "1981-09-03T11:56:24+08:00",
              "utc": "1981-09-03T03:56:24Z",
              "ms": 368337384376.08887
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 00:00 on Tue 1 Sep to 01:30 on Thu 3 Sep.",
          "fact": "1981-09-01T15:59:46Z → 1981-09-02T17:29:38Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:09–11:57 on the 2nd, 11:08–11:56 on the 3rd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 48 of 48 minutes on the 2nd and 0 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 34726 s"
        },
        {
          "step": "ruling",
          "text": "Gaṇeśa Caturthī, Harbin, 1981: Wednesday 2 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ganesha-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 4 Varada caturthi (purvaviddha, madhyahnavyapini), Samvatsari parva (Jain-caturthi paksa), Saubhagya caturthi (Bengal), Ganesa caturthi (madhyahna vyapini and purvaviddha)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Gaṇeśa Caturthī 1981 falls on Wednesday 2 September. Caturthī runs from 00:00 on Tue 1 Sep to 01:30 on Thu 3 Sep and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ganesha-chaturthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/rishi-panchami",
      "festival": "rishi-panchami",
      "name": "Ṛṣi Pañcamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-03",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 27627,
      "anga": {
        "type": "tithi",
        "index": 4,
        "key": "panchami",
        "name": "Pañcamī",
        "start": {
          "local": "1981-09-03T01:29:38+08:00",
          "utc": "1981-09-02T17:29:38Z",
          "ms": 368299778069.4927
        },
        "end": {
          "local": "1981-09-04T03:27:37+08:00",
          "utc": "1981-09-03T19:27:37Z",
          "ms": 368393257437.3487
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-03T01:29:38+08:00",
          "utc": "1981-09-02T17:29:38Z",
          "ms": 368299778069.4927
        },
        "end": {
          "local": "1981-09-04T03:27:37+08:00",
          "utc": "1981-09-03T19:27:37Z",
          "ms": 368393257437.3487
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-09-03",
          "window": {
            "start": {
              "local": "1981-09-03T11:08:24+08:00",
              "utc": "1981-09-03T03:08:24Z",
              "ms": 368334504376.08887
            },
            "end": {
              "local": "1981-09-03T11:56:24+08:00",
              "utc": "1981-09-03T03:56:24Z",
              "ms": 368337384376.08887
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-09-04",
          "window": {
            "start": {
              "local": "1981-09-04T11:08:05+08:00",
              "utc": "1981-09-04T03:08:05Z",
              "ms": 368420884889.51746
            },
            "end": {
              "local": "1981-09-04T11:56:05+08:00",
              "utc": "1981-09-04T03:56:05Z",
              "ms": 368423764889.51746
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pañcamī runs from 01:30 on Thu 3 Sep to 03:28 on Fri 4 Sep.",
          "fact": "1981-09-02T17:29:38Z → 1981-09-03T19:27:37Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:08–11:56 on the 3rd, 11:08–11:56 on the 4th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pañcamī must be present during madhyāhna. It covers 48 of 48 minutes on the 3rd and 0 of 48 on the 4th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: disputed → only-day · margin 27627 s"
        },
        {
          "step": "ruling",
          "text": "Ṛṣi Pañcamī, Harbin, 1981: Thursday 3 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "rishi-panchami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 5 Rsi pancami (madhyahnavyapini) — If occurs on two successive days, it is to be observed according to Madhava on the 1st day and according to Hemadri and Divodasa on the 2nd day"
          }
        ],
        "kaala": "madhyahna",
        "priority": "disputed",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-03",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-03",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Ṛṣi Pañcamī 1981 falls on Thursday 3 September. Pañcamī runs from 01:30 on Thu 3 Sep to 03:28 on Fri 4 Sep and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/rishi-panchami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/surya-shashthi-bhadrapada",
      "festival": "surya-shashthi-bhadrapada",
      "name": "Sūrya Ṣaṣṭhī (Bhādrapada)",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-04",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 19312,
      "anga": {
        "type": "tithi",
        "index": 5,
        "key": "shashthi",
        "name": "Ṣaṣṭhī",
        "start": {
          "local": "1981-09-04T03:27:37+08:00",
          "utc": "1981-09-03T19:27:37Z",
          "ms": 368393257437.3487
        },
        "end": {
          "local": "1981-09-05T05:45:53+08:00",
          "utc": "1981-09-04T21:45:53Z",
          "ms": 368487952691.1875
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-04T03:27:37+08:00",
          "utc": "1981-09-03T19:27:37Z",
          "ms": 368393257437.3487
        },
        "end": {
          "local": "1981-09-05T05:45:53+08:00",
          "utc": "1981-09-04T21:45:53Z",
          "ms": 368487952691.1875
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-09-04",
          "window": {
            "start": {
              "local": "1981-09-04T11:08:05+08:00",
              "utc": "1981-09-04T03:08:05Z",
              "ms": 368420884889.51746
            },
            "end": {
              "local": "1981-09-04T11:56:05+08:00",
              "utc": "1981-09-04T03:56:05Z",
              "ms": 368423764889.51746
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-09-05",
          "window": {
            "start": {
              "local": "1981-09-05T11:07:45+08:00",
              "utc": "1981-09-05T03:07:45Z",
              "ms": 368507265143.96783
            },
            "end": {
              "local": "1981-09-05T11:55:45+08:00",
              "utc": "1981-09-05T03:55:45Z",
              "ms": 368510145143.96783
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ṣaṣṭhī runs from 03:28 on Fri 4 Sep to 05:46 on Sat 5 Sep.",
          "fact": "1981-09-03T19:27:37Z → 1981-09-04T21:45:53Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:08–11:56 on the 4th, 11:08–11:56 on the 5th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ṣaṣṭhī must be present during madhyāhna. It covers 48 of 48 minutes on the 4th and 0 of 48 on the 5th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 19312 s"
        },
        {
          "step": "ruling",
          "text": "Sūrya Ṣaṣṭhī (Bhādrapada), Harbin, 1981: Friday 4 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "surya-shashthi-bhadrapada",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 6 Surya sasthi (paraviddha), Lolarka sasthi"
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-04",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-04",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Sūrya Ṣaṣṭhī (Bhādrapada) 1981 falls on Friday 4 September. Ṣaṣṭhī runs from 03:28 on Fri 4 Sep to 05:46 on Sat 5 Sep and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/surya-shashthi-bhadrapada",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/muktabharana-vrata",
      "festival": "muktabharana-vrata",
      "name": "Muktābharaṇa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-05",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 10467,
      "anga": {
        "type": "tithi",
        "index": 6,
        "key": "saptami",
        "name": "Saptamī",
        "start": {
          "local": "1981-09-05T05:45:53+08:00",
          "utc": "1981-09-04T21:45:53Z",
          "ms": 368487952691.1875
        },
        "end": {
          "local": "1981-09-06T08:12:58+08:00",
          "utc": "1981-09-06T00:12:58Z",
          "ms": 368583177767.79974
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-05T05:45:53+08:00",
          "utc": "1981-09-04T21:45:53Z",
          "ms": 368487952691.1875
        },
        "end": {
          "local": "1981-09-06T08:12:58+08:00",
          "utc": "1981-09-06T00:12:58Z",
          "ms": 368583177767.79974
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-09-05",
          "window": {
            "start": {
              "local": "1981-09-05T11:07:45+08:00",
              "utc": "1981-09-05T03:07:45Z",
              "ms": 368507265143.96783
            },
            "end": {
              "local": "1981-09-05T11:55:45+08:00",
              "utc": "1981-09-05T03:55:45Z",
              "ms": 368510145143.96783
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-09-06",
          "window": {
            "start": {
              "local": "1981-09-06T11:07:25+08:00",
              "utc": "1981-09-06T03:07:25Z",
              "ms": 368593645156.2038
            },
            "end": {
              "local": "1981-09-06T11:55:25+08:00",
              "utc": "1981-09-06T03:55:25Z",
              "ms": 368596525156.2038
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Saptamī runs from 05:46 on Sat 5 Sep to 08:13 on Sun 6 Sep.",
          "fact": "1981-09-04T21:45:53Z → 1981-09-06T00:12:58Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:08–11:56 on the 5th, 11:07–11:55 on the 6th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Saptamī must be present during madhyāhna. It covers 48 of 48 minutes on the 5th and 0 of 48 on the 6th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 10467 s"
        },
        {
          "step": "ruling",
          "text": "Muktābharaṇa Vrata, Harbin, 1981: Saturday 5 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "muktabharana-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 7 Muktabharana vrata (purvaviddha), Lalita saptami (Bengal & Orissa)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-05",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-05",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Muktābharaṇa Vrata 1981 falls on Saturday 5 September. Saptamī runs from 05:46 on Sat 5 Sep to 08:13 on Sun 6 Sep and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/muktabharana-vrata",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/radhashtami",
      "festival": "radhashtami",
      "name": "Rādhāṣṭamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-06",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1921,
      "anga": {
        "type": "tithi",
        "index": 7,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-09-06T08:12:58+08:00",
          "utc": "1981-09-06T00:12:58Z",
          "ms": 368583177767.79974
        },
        "end": {
          "local": "1981-09-07T10:35:04+08:00",
          "utc": "1981-09-07T02:35:04Z",
          "ms": 368678103500.8203
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-06T08:12:58+08:00",
          "utc": "1981-09-06T00:12:58Z",
          "ms": 368583177767.79974
        },
        "end": {
          "local": "1981-09-07T10:35:04+08:00",
          "utc": "1981-09-07T02:35:04Z",
          "ms": 368678103500.8203
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-09-06",
          "window": {
            "start": {
              "local": "1981-09-06T11:07:25+08:00",
              "utc": "1981-09-06T03:07:25Z",
              "ms": 368593645156.2038
            },
            "end": {
              "local": "1981-09-06T11:55:25+08:00",
              "utc": "1981-09-06T03:55:25Z",
              "ms": 368596525156.2038
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-09-07",
          "window": {
            "start": {
              "local": "1981-09-07T11:07:05+08:00",
              "utc": "1981-09-07T03:07:05Z",
              "ms": 368680024943.69824
            },
            "end": {
              "local": "1981-09-07T11:55:05+08:00",
              "utc": "1981-09-07T03:55:05Z",
              "ms": 368682904943.69824
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 08:13 on Sun 6 Sep to 10:35 on Mon 7 Sep.",
          "fact": "1981-09-06T00:12:58Z → 1981-09-07T02:35:04Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:07–11:55 on the 6th, 11:07–11:55 on the 7th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be present during madhyāhna. It covers 48 of 48 minutes on the 6th and 0 of 48 on the 7th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 1921 s"
        },
        {
          "step": "ruling",
          "text": "Rādhāṣṭamī, Harbin, 1981: Sunday 6 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "radhashtami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 8 Durvastami (purvaviddha — S 8 of saura Bhadra except Bengal), Mahalaksmi vratarambha, Radhastami (madhyahna vyapini)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-06",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-06",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Rādhāṣṭamī 1981 falls on Sunday 6 September. Aṣṭamī runs from 08:13 on Sun 6 Sep to 10:35 on Mon 7 Sep and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/radhashtami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-09-10",
      "festival": "ekadashi",
      "name": "Parivartanī Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-10",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 32722,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-09-09T14:09:09+08:00",
          "utc": "1981-09-09T06:09:09Z",
          "ms": 368863748879.2041
        },
        "end": {
          "local": "1981-09-10T14:59:49+08:00",
          "utc": "1981-09-10T06:59:49Z",
          "ms": 368953188643.5851
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-09T14:09:09+08:00",
          "utc": "1981-09-09T06:09:09Z",
          "ms": 368863748879.2041
        },
        "end": {
          "local": "1981-09-10T14:59:49+08:00",
          "utc": "1981-09-10T06:59:49Z",
          "ms": 368953188643.5851
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-09-09",
          "window": {
            "start": {
              "local": "1981-09-09T05:03:47+08:00",
              "utc": "1981-09-08T21:03:47Z",
              "ms": 368831026729.1306
            },
            "end": {
              "local": "1981-09-09T05:03:47+08:00",
              "utc": "1981-09-08T21:03:47Z",
              "ms": 368831026729.1306
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-09-10",
          "window": {
            "start": {
              "local": "1981-09-10T05:05:01+08:00",
              "utc": "1981-09-09T21:05:01Z",
              "ms": 368917500605.3638
            },
            "end": {
              "local": "1981-09-10T05:05:01+08:00",
              "utc": "1981-09-09T21:05:01Z",
              "ms": 368917500605.3638
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 14:09 on Wed 9 Sep to 15:00 on Thu 10 Sep.",
          "fact": "1981-09-09T06:09:09Z → 1981-09-10T06:59:49Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 05:04 on the 9th and 05:05 on the 10th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 9th and is on the 10th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 32722 s"
        },
        {
          "step": "ruling",
          "text": "Parivartanī Ekādaśī, Harbin, 1981: Thursday 10 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-10",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-10",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Parivartanī Ekādaśī 1981 falls on Thursday 10 September. Ekādaśī runs from 14:09 on Wed 9 Sep to 15:00 on Thu 10 Sep and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-09-10",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vamana-jayanti",
      "festival": "vamana-jayanti",
      "name": "Vāmana Jayantī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 11146,
      "anga": {
        "type": "tithi",
        "index": 11,
        "key": "dvadashi",
        "name": "Dvādaśī",
        "start": {
          "local": "1981-09-10T14:59:49+08:00",
          "utc": "1981-09-10T06:59:49Z",
          "ms": 368953188643.5851
        },
        "end": {
          "local": "1981-09-11T15:05:27+08:00",
          "utc": "1981-09-11T07:05:27Z",
          "ms": 369039927068.0516
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-10T14:59:49+08:00",
          "utc": "1981-09-10T06:59:49Z",
          "ms": 368953188643.5851
        },
        "end": {
          "local": "1981-09-11T15:05:27+08:00",
          "utc": "1981-09-11T07:05:27Z",
          "ms": 369039927068.0516
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-09-10",
          "window": {
            "start": {
              "local": "1981-09-10T11:06:03+08:00",
              "utc": "1981-09-10T03:06:03Z",
              "ms": 368939163143.0355
            },
            "end": {
              "local": "1981-09-10T11:54:03+08:00",
              "utc": "1981-09-10T03:54:03Z",
              "ms": 368942043143.0355
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-09-11",
          "window": {
            "start": {
              "local": "1981-09-11T11:05:42+08:00",
              "utc": "1981-09-11T03:05:42Z",
              "ms": 369025542220.6116
            },
            "end": {
              "local": "1981-09-11T11:53:42+08:00",
              "utc": "1981-09-11T03:53:42Z",
              "ms": 369028422220.6116
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvādaśī runs from 15:00 on Thu 10 Sep to 15:05 on Fri 11 Sep.",
          "fact": "1981-09-10T06:59:49Z → 1981-09-11T07:05:27Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:06–11:54 on the 10th, 11:06–11:54 on the 11th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvādaśī must be present during madhyāhna. It covers 0 of 48 minutes on the 10th and 48 of 48 on the 11th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 11146 s"
        },
        {
          "step": "ruling",
          "text": "Vāmana Jayantī, Harbin, 1981: Friday 11 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vamana-jayanti",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 12 Visnuparivartanotsava, Sakrotthana (in any of the naksatras U. Asadha, Sravana & Dhanistha), Kalki dvadasi, Sravana dvadasi (when combined with naksatra Sravana), Vamana jayanti (madhyahna vyapini)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vāmana Jayantī 1981 falls on Friday 11 September. Dvādaśī runs from 15:00 on Thu 10 Sep to 15:05 on Fri 11 Sep and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vamana-jayanti",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-09-11",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 10063,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-09-11T15:05:27+08:00",
          "utc": "1981-09-11T07:05:27Z",
          "ms": 369039927068.0516
        },
        "end": {
          "local": "1981-09-12T14:25:58+08:00",
          "utc": "1981-09-12T06:25:58Z",
          "ms": 369123958286.36127
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-11T15:05:27+08:00",
          "utc": "1981-09-11T07:05:27Z",
          "ms": 369039927068.0516
        },
        "end": {
          "local": "1981-09-12T14:25:58+08:00",
          "utc": "1981-09-12T06:25:58Z",
          "ms": 369123958286.36127
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-09-11",
          "window": {
            "start": {
              "local": "1981-09-11T17:53:10+08:00",
              "utc": "1981-09-11T09:53:10Z",
              "ms": 369049989958.07794
            },
            "end": {
              "local": "1981-09-11T19:23:04+08:00",
              "utc": "1981-09-11T11:23:04Z",
              "ms": 369055384413.3469
            }
          },
          "covered_min": 90,
          "window_min": 90,
          "qualifies": true
        },
        {
          "local_date": "1981-09-12",
          "window": {
            "start": {
              "local": "1981-09-12T17:51:14+08:00",
              "utc": "1981-09-12T09:51:14Z",
              "ms": 369136273971.2002
            },
            "end": {
              "local": "1981-09-12T19:21:34+08:00",
              "utc": "1981-09-12T11:21:34Z",
              "ms": 369141693746.4412
            }
          },
          "covered_min": 0,
          "window_min": 90,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 15:05 on Fri 11 Sep to 14:26 on Sat 12 Sep.",
          "fact": "1981-09-11T07:05:27Z → 1981-09-12T06:25:58Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 17:53–19:23 on the 11th, 17:51–19:22 on the 12th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 90 of 90 minutes on the 11th and 0 of 90 on the 12th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 10063 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Friday 11 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Friday 11 September. Trayodaśī runs from 15:05 on Fri 11 Sep to 14:26 on Sat 12 Sep and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-09-11",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ananta-chaturdashi",
      "festival": "ananta-chaturdashi",
      "name": "Ananta Caturdaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-13",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 19448,
      "anga": {
        "type": "tithi",
        "index": 13,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-09-12T14:25:58+08:00",
          "utc": "1981-09-12T06:25:58Z",
          "ms": 369123958286.36127
        },
        "end": {
          "local": "1981-09-13T13:04:57+08:00",
          "utc": "1981-09-13T05:04:57Z",
          "ms": 369205497313.9881
        },
        "month": {
          "amanta": 5,
          "purnimanta": 5,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Bhādrapada"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-12T14:25:58+08:00",
          "utc": "1981-09-12T06:25:58Z",
          "ms": 369123958286.36127
        },
        "end": {
          "local": "1981-09-13T13:04:57+08:00",
          "utc": "1981-09-13T05:04:57Z",
          "ms": 369205497313.9881
        }
      },
      "kaala": "udaya-3",
      "days": [
        {
          "local_date": "1981-09-12",
          "window": {
            "start": {
              "local": "1981-09-12T05:07:28+08:00",
              "utc": "1981-09-11T21:07:28Z",
              "ms": 369090448372.5953
            },
            "end": {
              "local": "1981-09-12T07:40:13+08:00",
              "utc": "1981-09-11T23:40:13Z",
              "ms": 369099613492.3163
            }
          },
          "covered_min": 0,
          "window_min": 153,
          "qualifies": false
        },
        {
          "local_date": "1981-09-13",
          "window": {
            "start": {
              "local": "1981-09-13T05:08:42+08:00",
              "utc": "1981-09-12T21:08:42Z",
              "ms": 369176922285.5078
            },
            "end": {
              "local": "1981-09-13T07:40:49+08:00",
              "utc": "1981-09-12T23:40:49Z",
              "ms": 369186049378.94464
            }
          },
          "covered_min": 152,
          "window_min": 152,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 14:26 on Sat 12 Sep to 13:05 on Sun 13 Sep.",
          "fact": "1981-09-12T06:25:58Z → 1981-09-13T05:04:57Z"
        },
        {
          "step": "kaala",
          "text": "The first three muhūrtas after sunrise is first 3 of 15 day muhūrtas: 05:07–07:40 on the 12th, 05:09–07:41 on the 13th.",
          "fact": "udaya-3: day-muhurta-1-3 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must hold through the first three muhūrtas after sunrise. It covers 0 of 153 minutes on the 12th and 152 of 152 on the 13th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one morning qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 19448 s"
        },
        {
          "step": "ruling",
          "text": "Ananta Caturdaśī, Harbin, 1981: Sunday 13 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ananta-chaturdashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 14 Ananta caturdasi (covering three muhurtas from sunrise, but one muhurta in Bengal)."
          }
        ],
        "not_evaluated": "In Bengal the row asks for one muhūrta from sunrise; that reading is not applied.",
        "kaala": "udaya-3",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-13",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-13",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Ananta Caturdaśī 1981 falls on Sunday 13 September. Caturdaśī runs from 14:26 on Sat 12 Sep to 13:05 on Sun 13 Sep and covers all of the first three muhūrtas after sunrise that morning.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ananta-chaturdashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-09-17",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-17",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 16446,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-09-17T03:11:55+08:00",
          "utc": "1981-09-16T19:11:55Z",
          "ms": 369515514971.6247
        },
        "end": {
          "local": "1981-09-18T00:19:41+08:00",
          "utc": "1981-09-17T16:19:41Z",
          "ms": 369591581067.99927
        },
        "month": {
          "amanta": 5,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-17T03:11:55+08:00",
          "utc": "1981-09-16T19:11:55Z",
          "ms": 369515514971.6247
        },
        "end": {
          "local": "1981-09-18T00:19:41+08:00",
          "utc": "1981-09-17T16:19:41Z",
          "ms": 369591581067.99927
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-09-16",
          "window": {
            "start": {
              "local": "1981-09-16T19:14:31+08:00",
              "utc": "1981-09-16T11:14:31Z",
              "ms": 369486871478.4059
            },
            "end": {
              "local": "1981-09-16T19:14:31+08:00",
              "utc": "1981-09-16T11:14:31Z",
              "ms": 369486871478.4059
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-09-17",
          "window": {
            "start": {
              "local": "1981-09-17T19:45:35+08:00",
              "utc": "1981-09-17T11:45:35Z",
              "ms": 369575134928.88837
            },
            "end": {
              "local": "1981-09-17T19:45:35+08:00",
              "utc": "1981-09-17T11:45:35Z",
              "ms": 369575134928.88837
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 03:12 on Thu 17 Sep to 00:20 on Fri 18 Sep.",
          "fact": "1981-09-16T19:11:55Z → 1981-09-17T16:19:41Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 19:15 on the 16th and 19:46 on the 17th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is not on the 16th and is on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 16446 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Thursday 17 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-17",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-17",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Thursday 17 September. Caturthī runs from 03:12 on Thu 17 Sep to 00:20 on Fri 18 Sep and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-09-17",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/chandra-shashthi",
      "festival": "chandra-shashthi",
      "name": "Candra Ṣaṣṭhī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-18",
      "confidence": "boundary",
      "boundary_reasons": [
        "absent-unstated"
      ],
      "boundary_margin_s": 4454,
      "anga": {
        "type": "tithi",
        "index": 20,
        "key": "shashthi",
        "name": "Ṣaṣṭhī",
        "start": {
          "local": "1981-09-18T21:34:11+08:00",
          "utc": "1981-09-18T13:34:11Z",
          "ms": 369668050715.8048
        },
        "end": {
          "local": "1981-09-19T19:01:43+08:00",
          "utc": "1981-09-19T11:01:43Z",
          "ms": 369745302810.6584
        },
        "month": {
          "amanta": 5,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-18T21:34:11+08:00",
          "utc": "1981-09-18T13:34:11Z",
          "ms": 369668050715.8048
        },
        "end": {
          "local": "1981-09-19T19:01:43+08:00",
          "utc": "1981-09-19T11:01:43Z",
          "ms": 369745302810.6584
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-09-18",
          "window": {
            "start": {
              "local": "1981-09-18T20:19:57+08:00",
              "utc": "1981-09-18T12:19:57Z",
              "ms": 369663596785.08203
            },
            "end": {
              "local": "1981-09-18T20:19:57+08:00",
              "utc": "1981-09-18T12:19:57Z",
              "ms": 369663596785.08203
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-09-19",
          "window": {
            "start": {
              "local": "1981-09-19T20:59:16+08:00",
              "utc": "1981-09-19T12:59:16Z",
              "ms": 369752355662.9231
            },
            "end": {
              "local": "1981-09-19T20:59:16+08:00",
              "utc": "1981-09-19T12:59:16Z",
              "ms": 369752355662.9231
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "tithi-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ṣaṣṭhī runs from 21:34 on Fri 18 Sep to 19:02 on Sat 19 Sep.",
          "fact": "1981-09-18T13:34:11Z → 1981-09-19T11:01:43Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 20:20 on the 18th and 20:59 on the 19th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Ṣaṣṭhī must be current at moonrise. It is not on the 18th and is not on the 19th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Neither moonrise qualifies. The day the tithi falls on is taken.",
          "fact": "priority: purvaviddha → tithi-day · margin 4454 s"
        },
        {
          "step": "ruling",
          "text": "Candra Ṣaṣṭhī, Harbin, 1981: Friday 18 September.",
          "fact": "confidence: boundary (absent-unstated)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "chandra-shashthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 6 Candra sasthi (Sasthi current at moon-rise, if occurs on two successive days, it is to be observed on the first day)."
          }
        ],
        "kaala": "moonrise",
        "priority": "purvaviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-18",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-18",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Candra Ṣaṣṭhī 1981 falls on Friday 18 September. Ṣaṣṭhī runs from 21:34 on Fri 18 Sep to 19:02 on Sat 19 Sep, and is current at moonrise on neither day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/chandra-shashthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/jitashtami",
      "festival": "jitashtami",
      "name": "Jitāṣṭamī",
      "everyday": "Jitiya",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-20",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2918,
      "anga": {
        "type": "tithi",
        "index": 22,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-09-20T16:47:02+08:00",
          "utc": "1981-09-20T08:47:02Z",
          "ms": 369823622285.6271
        },
        "end": {
          "local": "1981-09-21T14:53:14+08:00",
          "utc": "1981-09-21T06:53:14Z",
          "ms": 369903194181.50146
        },
        "month": {
          "amanta": 5,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-20T16:47:02+08:00",
          "utc": "1981-09-20T08:47:02Z",
          "ms": 369823622285.6271
        },
        "end": {
          "local": "1981-09-21T14:53:14+08:00",
          "utc": "1981-09-21T06:53:14Z",
          "ms": 369903194181.50146
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-09-20",
          "window": {
            "start": {
              "local": "1981-09-20T17:35:40+08:00",
              "utc": "1981-09-20T09:35:40Z",
              "ms": 369826540450.35803
            },
            "end": {
              "local": "1981-09-20T19:09:24+08:00",
              "utc": "1981-09-20T11:09:24Z",
              "ms": 369832163889.4902
            }
          },
          "covered_min": 94,
          "window_min": 94,
          "qualifies": true
        },
        {
          "local_date": "1981-09-21",
          "window": {
            "start": {
              "local": "1981-09-21T17:33:44+08:00",
              "utc": "1981-09-21T09:33:44Z",
              "ms": 369912823533.0685
            },
            "end": {
              "local": "1981-09-21T19:07:53+08:00",
              "utc": "1981-09-21T11:07:53Z",
              "ms": 369918472534.41315
            }
          },
          "covered_min": 0,
          "window_min": 94,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 16:47 on Sun 20 Sep to 14:53 on Mon 21 Sep.",
          "fact": "1981-09-20T08:47:02Z → 1981-09-21T06:53:14Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 17:36–19:09 on the 20th, 17:34–19:08 on the 21st.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be present during pradoṣa. It covers 94 of 94 minutes on the 20th and 0 of 94 on the 21st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 2918 s"
        },
        {
          "step": "ruling",
          "text": "Jitāṣṭamī, Harbin, 1981: Sunday 20 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "jitashtami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 8 Mahalaksmi vrata samapana (current at moonrise), Jitastami (pradosa), Jimutavahana puja"
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-20",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-20",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Jitāṣṭamī (Jitiya) 1981 falls on Sunday 20 September. Aṣṭamī runs from 16:47 on Sun 20 Sep to 14:53 on Mon 21 Sep and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/jitashtami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/mahalakshmi-vrata-samapana",
      "festival": "mahalakshmi-vrata-samapana",
      "name": "Mahālakṣmī Vrata Samāpana",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-20",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 17876,
      "anga": {
        "type": "tithi",
        "index": 22,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-09-20T16:47:02+08:00",
          "utc": "1981-09-20T08:47:02Z",
          "ms": 369823622285.6271
        },
        "end": {
          "local": "1981-09-21T14:53:14+08:00",
          "utc": "1981-09-21T06:53:14Z",
          "ms": 369903194181.50146
        },
        "month": {
          "amanta": 5,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-20T16:47:02+08:00",
          "utc": "1981-09-20T08:47:02Z",
          "ms": 369823622285.6271
        },
        "end": {
          "local": "1981-09-21T14:53:14+08:00",
          "utc": "1981-09-21T06:53:14Z",
          "ms": 369903194181.50146
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-09-20",
          "window": {
            "start": {
              "local": "1981-09-20T21:44:58+08:00",
              "utc": "1981-09-20T13:44:58Z",
              "ms": 369841498068.69586
            },
            "end": {
              "local": "1981-09-20T21:44:58+08:00",
              "utc": "1981-09-20T13:44:58Z",
              "ms": 369841498068.69586
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-09-21",
          "window": {
            "start": {
              "local": "1981-09-21T22:37:48+08:00",
              "utc": "1981-09-21T14:37:48Z",
              "ms": 369931067554.6845
            },
            "end": {
              "local": "1981-09-21T22:37:48+08:00",
              "utc": "1981-09-21T14:37:48Z",
              "ms": 369931067554.6845
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 16:47 on Sun 20 Sep to 14:53 on Mon 21 Sep.",
          "fact": "1981-09-20T08:47:02Z → 1981-09-21T06:53:14Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 21:45 on the 20th and 22:38 on the 21st.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be current at moonrise. It is on the 20th and is not on the 21st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 17876 s"
        },
        {
          "step": "ruling",
          "text": "Mahālakṣmī Vrata Samāpana, Harbin, 1981: Sunday 20 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "mahalakshmi-vrata-samapana",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 8 Mahalaksmi vrata samapana (current at moonrise), Jitastami (pradosa), Jimutavahana puja"
          }
        ],
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-20",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-20",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Mahālakṣmī Vrata Samāpana 1981 falls on Sunday 20 September. Aṣṭamī runs from 16:47 on Sun 20 Sep to 14:53 on Mon 21 Sep and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/mahalakshmi-vrata-samapana",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-09-24",
      "festival": "ekadashi",
      "name": "Indirā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-24",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 21882,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-09-23T12:13:13+08:00",
          "utc": "1981-09-23T04:13:13Z",
          "ms": 370066393325.7998
        },
        "end": {
          "local": "1981-09-24T11:27:03+08:00",
          "utc": "1981-09-24T03:27:03Z",
          "ms": 370150023458.8285
        },
        "month": {
          "amanta": 5,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-23T12:13:13+08:00",
          "utc": "1981-09-23T04:13:13Z",
          "ms": 370066393325.7998
        },
        "end": {
          "local": "1981-09-24T11:27:03+08:00",
          "utc": "1981-09-24T03:27:03Z",
          "ms": 370150023458.8285
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-09-23",
          "window": {
            "start": {
              "local": "1981-09-23T05:21:06+08:00",
              "utc": "1981-09-22T21:21:06Z",
              "ms": 370041666004.2933
            },
            "end": {
              "local": "1981-09-23T05:21:06+08:00",
              "utc": "1981-09-22T21:21:06Z",
              "ms": 370041666004.2933
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-09-24",
          "window": {
            "start": {
              "local": "1981-09-24T05:22:21+08:00",
              "utc": "1981-09-23T21:22:21Z",
              "ms": 370128141135.21936
            },
            "end": {
              "local": "1981-09-24T05:22:21+08:00",
              "utc": "1981-09-23T21:22:21Z",
              "ms": 370128141135.21936
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 12:13 on Wed 23 Sep to 11:27 on Thu 24 Sep.",
          "fact": "1981-09-23T04:13:13Z → 1981-09-24T03:27:03Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 05:21 on the 23rd and 05:22 on the 24th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 23rd and is on the 24th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 21882 s"
        },
        {
          "step": "ruling",
          "text": "Indirā Ekādaśī, Harbin, 1981: Thursday 24 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-24",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-24",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Indirā Ekādaśī 1981 falls on Thursday 24 September. Ekādaśī runs from 12:13 on Wed 23 Sep to 11:27 on Thu 24 Sep and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-09-24",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-09-25",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-25",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 22975,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-09-25T11:03:00+08:00",
          "utc": "1981-09-25T03:03:00Z",
          "ms": 370234979628.1569
        },
        "end": {
          "local": "1981-09-26T11:01:06+08:00",
          "utc": "1981-09-26T03:01:06Z",
          "ms": 370321265798.51874
        },
        "month": {
          "amanta": 5,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-25T11:03:00+08:00",
          "utc": "1981-09-25T03:03:00Z",
          "ms": 370234979628.1569
        },
        "end": {
          "local": "1981-09-26T11:01:06+08:00",
          "utc": "1981-09-26T03:01:06Z",
          "ms": 370321265798.51874
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-09-25",
          "window": {
            "start": {
              "local": "1981-09-25T17:25:57+08:00",
              "utc": "1981-09-25T09:25:57Z",
              "ms": 370257956671.1867
            },
            "end": {
              "local": "1981-09-25T19:01:48+08:00",
              "utc": "1981-09-25T11:01:48Z",
              "ms": 370263708039.6204
            }
          },
          "covered_min": 96,
          "window_min": 96,
          "qualifies": true
        },
        {
          "local_date": "1981-09-26",
          "window": {
            "start": {
              "local": "1981-09-26T17:24:00+08:00",
              "utc": "1981-09-26T09:24:00Z",
              "ms": 370344240299.91296
            },
            "end": {
              "local": "1981-09-26T19:00:17+08:00",
              "utc": "1981-09-26T11:00:17Z",
              "ms": 370350017275.325
            }
          },
          "covered_min": 0,
          "window_min": 96,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 11:03 on Fri 25 Sep to 11:01 on Sat 26 Sep.",
          "fact": "1981-09-25T03:03:00Z → 1981-09-26T03:01:06Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 17:26–19:02 on the 25th, 17:24–19:00 on the 26th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 96 of 96 minutes on the 25th and 0 of 96 on the 26th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 22975 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Friday 25 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-25",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-25",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Friday 25 September. Trayodaśī runs from 11:03 on Fri 25 Sep to 11:01 on Sat 26 Sep and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-09-25",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-09-26",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-26",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 40301,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-09-26T11:01:06+08:00",
          "utc": "1981-09-26T03:01:06Z",
          "ms": 370321265798.51874
        },
        "end": {
          "local": "1981-09-27T11:22:05+08:00",
          "utc": "1981-09-27T03:22:05Z",
          "ms": 370408925118.95844
        },
        "month": {
          "amanta": 5,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-26T11:01:06+08:00",
          "utc": "1981-09-26T03:01:06Z",
          "ms": 370321265798.51874
        },
        "end": {
          "local": "1981-09-27T11:22:05+08:00",
          "utc": "1981-09-27T03:22:05Z",
          "ms": 370408925118.95844
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-09-25",
          "window": {
            "start": {
              "local": "1981-09-25T23:01:24+08:00",
              "utc": "1981-09-25T15:01:24Z",
              "ms": 370278084302.81323
            },
            "end": {
              "local": "1981-09-25T23:49:24+08:00",
              "utc": "1981-09-25T15:49:24Z",
              "ms": 370280964302.81323
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-09-26",
          "window": {
            "start": {
              "local": "1981-09-26T23:01:04+08:00",
              "utc": "1981-09-26T15:01:04Z",
              "ms": 370364463957.708
            },
            "end": {
              "local": "1981-09-26T23:49:04+08:00",
              "utc": "1981-09-26T15:49:04Z",
              "ms": 370367343957.708
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 11:01 on Sat 26 Sep to 11:22 on Sun 27 Sep.",
          "fact": "1981-09-26T03:01:06Z → 1981-09-27T03:22:05Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:01–23:49 on the 25th, 23:01–23:49 on the 26th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 0 of 48 minutes on the 25th and 48 of 48 on the 26th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 40301 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Saturday 26 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-26",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-26",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Saturday 26 September. Caturdaśī runs from 11:01 on Sat 26 Sep to 11:22 on Sun 27 Sep and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-09-26",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/mahalaya-amavasya",
      "festival": "mahalaya-amavasya",
      "name": "Mahālaya Amāvāsyā",
      "everyday": "Sarvapitṛ Amāvāsyā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-27",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1670,
      "anga": {
        "type": "tithi",
        "index": 29,
        "key": "amavasya",
        "name": "Amāvasyā",
        "start": {
          "local": "1981-09-27T11:22:05+08:00",
          "utc": "1981-09-27T03:22:05Z",
          "ms": 370408925118.95844
        },
        "end": {
          "local": "1981-09-28T12:07:12+08:00",
          "utc": "1981-09-28T04:07:12Z",
          "ms": 370498032303.0421
        },
        "month": {
          "amanta": 5,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Bhādrapada",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-27T11:22:05+08:00",
          "utc": "1981-09-27T03:22:05Z",
          "ms": 370408925118.95844
        },
        "end": {
          "local": "1981-09-28T12:07:12+08:00",
          "utc": "1981-09-28T04:07:12Z",
          "ms": 370498032303.0421
        }
      },
      "kaala": "aparahna",
      "days": [
        {
          "local_date": "1981-09-27",
          "window": {
            "start": {
              "local": "1981-09-27T12:35:42+08:00",
              "utc": "1981-09-27T04:35:42Z",
              "ms": 370413341519.52966
            },
            "end": {
              "local": "1981-09-27T14:58:53+08:00",
              "utc": "1981-09-27T06:58:53Z",
              "ms": 370421932820.8719
            }
          },
          "covered_min": 143,
          "window_min": 143,
          "qualifies": true
        },
        {
          "local_date": "1981-09-28",
          "window": {
            "start": {
              "local": "1981-09-28T12:35:02+08:00",
              "utc": "1981-09-28T04:35:02Z",
              "ms": 370499702296.4861
            },
            "end": {
              "local": "1981-09-28T14:57:35+08:00",
              "utc": "1981-09-28T06:57:35Z",
              "ms": 370508255231.2419
            }
          },
          "covered_min": 0,
          "window_min": 143,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Amāvasyā runs from 11:22 on Sun 27 Sep to 12:07 on Mon 28 Sep.",
          "fact": "1981-09-27T03:22:05Z → 1981-09-28T04:07:12Z"
        },
        {
          "step": "kaala",
          "text": "Aparāhṇa is 10th to 12th of 15 day muhūrtas: 12:36–14:59 on the 27th, 12:35–14:58 on the 28th.",
          "fact": "aparahna: day-muhurta-10-12 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Amāvasyā must be present during aparāhṇa. It covers 143 of 143 minutes on the 27th and 0 of 143 on the 28th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103"
        },
        {
          "step": "tie_break",
          "text": "Only one afternoon qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 1670 s"
        },
        {
          "step": "ruling",
          "text": "Mahālaya Amāvāsyā, Harbin, 1981: Sunday 27 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "mahalaya-amavasya",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 103",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 30 Mahalaya amavasya (aparahnavyapini)"
          }
        ],
        "not_evaluated": "The note on p. 106 gives the first day in a decreasing tithimāna and the second in an increasing one, when amāvāsyā covers the whole of aparāhṇa on both days; tithimāna is not computed.",
        "kaala": "aparahna",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-27",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-27",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Mahālaya Amāvāsyā 1981 falls on Sunday 27 September. Amāvasyā runs from 11:22 on Sun 27 Sep to 12:07 on Mon 28 Sep and covers all of aparāhṇa that afternoon.",
      "cite": "https://ahargana.org/harbin/festivals/1981/mahalaya-amavasya",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/navaratra-arambha",
      "festival": "navaratra-arambha",
      "name": "Navarātrārambha",
      "everyday": "Navratri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-09-29",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1166,
      "anga": {
        "type": "tithi",
        "index": 0,
        "key": "pratipada",
        "name": "Pratipadā",
        "start": {
          "local": "1981-09-28T12:07:12+08:00",
          "utc": "1981-09-28T04:07:12Z",
          "ms": 370498032303.0421
        },
        "end": {
          "local": "1981-09-29T13:17:43+08:00",
          "utc": "1981-09-29T05:17:43Z",
          "ms": 370588663327.2907
        },
        "month": {
          "amanta": 6,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-09-28T12:07:12+08:00",
          "utc": "1981-09-28T04:07:12Z",
          "ms": 370498032303.0421
        },
        "end": {
          "local": "1981-09-29T13:17:43+08:00",
          "utc": "1981-09-29T05:17:43Z",
          "ms": 370588663327.2907
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-09-28",
          "window": {
            "start": {
              "local": "1981-09-28T10:59:46+08:00",
              "utc": "1981-09-28T02:59:46Z",
              "ms": 370493985829.1082
            },
            "end": {
              "local": "1981-09-28T11:47:46+08:00",
              "utc": "1981-09-28T03:47:46Z",
              "ms": 370496865829.1082
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-09-29",
          "window": {
            "start": {
              "local": "1981-09-29T10:59:26+08:00",
              "utc": "1981-09-29T02:59:26Z",
              "ms": 370580366014.92474
            },
            "end": {
              "local": "1981-09-29T11:47:26+08:00",
              "utc": "1981-09-29T03:47:26Z",
              "ms": 370583246014.92474
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pratipadā runs from 12:07 on Mon 28 Sep to 13:18 on Tue 29 Sep.",
          "fact": "1981-09-28T04:07:12Z → 1981-09-29T05:17:43Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:00–11:48 on the 28th, 10:59–11:47 on the 29th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pratipadā must be present during madhyāhna. It covers 0 of 48 minutes on the 28th and 48 of 48 on the 29th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 1166 s"
        },
        {
          "step": "ruling",
          "text": "Navarātrārambha, Harbin, 1981: Tuesday 29 September.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "navaratra-arambha",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 1 Navaratrarambha (paraviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-09-29",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-09-29",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Navarātrārambha (Navratri) 1981 falls on Tuesday 29 September. Pratipadā runs from 12:07 on Mon 28 Sep to 13:18 on Tue 29 Sep and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/navaratra-arambha",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-10-02",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-02",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 18486,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-10-01T16:54:53+08:00",
          "utc": "1981-10-01T08:54:53Z",
          "ms": 370774492901.53485
        },
        "end": {
          "local": "1981-10-02T19:15:48+08:00",
          "utc": "1981-10-02T11:15:48Z",
          "ms": 370869347868.8698
        },
        "month": {
          "amanta": 6,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-01T16:54:53+08:00",
          "utc": "1981-10-01T08:54:53Z",
          "ms": 370774492901.53485
        },
        "end": {
          "local": "1981-10-02T19:15:48+08:00",
          "utc": "1981-10-02T11:15:48Z",
          "ms": 370869347868.8698
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-10-01",
          "window": {
            "start": {
              "local": "1981-10-01T10:58:47+08:00",
              "utc": "1981-10-01T02:58:47Z",
              "ms": 370753127132.28296
            },
            "end": {
              "local": "1981-10-01T11:46:47+08:00",
              "utc": "1981-10-01T03:46:47Z",
              "ms": 370756007132.28296
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-10-02",
          "window": {
            "start": {
              "local": "1981-10-02T10:58:28+08:00",
              "utc": "1981-10-02T02:58:28Z",
              "ms": 370839508099.2446
            },
            "end": {
              "local": "1981-10-02T11:46:28+08:00",
              "utc": "1981-10-02T03:46:28Z",
              "ms": 370842388099.2446
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 16:55 on Thu 1 Oct to 19:16 on Fri 2 Oct.",
          "fact": "1981-10-01T08:54:53Z → 1981-10-02T11:15:48Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:59–11:47 on the 1st, 10:58–11:46 on the 2nd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 0 of 48 minutes on the 1st and 48 of 48 on the 2nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 18486 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Friday 2 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-02",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-02",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Friday 2 October. Caturthī runs from 16:55 on Thu 1 Oct to 19:16 on Fri 2 Oct and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-10-02",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/durga-saptami",
      "festival": "durga-saptami",
      "name": "Durgā Saptamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-05",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 10417,
      "anga": {
        "type": "tithi",
        "index": 6,
        "key": "saptami",
        "name": "Saptamī",
        "start": {
          "local": "1981-10-05T00:22:57+08:00",
          "utc": "1981-10-04T16:22:57Z",
          "ms": 371060577496.8392
        },
        "end": {
          "local": "1981-10-06T02:44:01+08:00",
          "utc": "1981-10-05T18:44:01Z",
          "ms": 371155441123.88776
        },
        "month": {
          "amanta": 6,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-05T00:22:57+08:00",
          "utc": "1981-10-04T16:22:57Z",
          "ms": 371060577496.8392
        },
        "end": {
          "local": "1981-10-06T02:44:01+08:00",
          "utc": "1981-10-05T18:44:01Z",
          "ms": 371155441123.88776
        }
      },
      "kaala": "udaya-1",
      "days": [
        {
          "local_date": "1981-10-05",
          "window": {
            "start": {
              "local": "1981-10-05T05:36:21+08:00",
              "utc": "1981-10-04T21:36:21Z",
              "ms": 371079380594.77454
            },
            "end": {
              "local": "1981-10-05T06:22:22+08:00",
              "utc": "1981-10-04T22:22:22Z",
              "ms": 371082142228.6828
            }
          },
          "covered_min": 46,
          "window_min": 46,
          "qualifies": true
        },
        {
          "local_date": "1981-10-06",
          "window": {
            "start": {
              "local": "1981-10-06T05:37:38+08:00",
              "utc": "1981-10-05T21:37:38Z",
              "ms": 371165858245.33435
            },
            "end": {
              "local": "1981-10-06T06:23:27+08:00",
              "utc": "1981-10-05T22:23:27Z",
              "ms": 371168607160.7147
            }
          },
          "covered_min": 0,
          "window_min": 46,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Saptamī runs from 00:23 on Mon 5 Oct to 02:44 on Tue 6 Oct.",
          "fact": "1981-10-04T16:22:57Z → 1981-10-05T18:44:01Z"
        },
        {
          "step": "kaala",
          "text": "The first muhūrta after sunrise is 1st of 15 day muhūrtas: 05:36–06:22 on the 5th, 05:38–06:23 on the 6th.",
          "fact": "udaya-1: day-muhurta-1-1 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Saptamī must hold through the first muhūrta after sunrise. It covers 46 of 46 minutes on the 5th and 0 of 46 on the 6th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one morning qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 10417 s"
        },
        {
          "step": "ruling",
          "text": "Durgā Saptamī, Harbin, 1981: Monday 5 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "durga-saptami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 7 Durga saptami (paraviddha) — covering one muhurta from sunrise"
          }
        ],
        "kaala": "udaya-1",
        "priority": "paraviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-05",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-05",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Durgā Saptamī 1981 falls on Monday 5 October. Saptamī runs from 00:23 on Mon 5 Oct to 02:44 on Tue 6 Oct and covers all of the first muhūrta after sunrise that morning.",
      "cite": "https://ahargana.org/harbin/festivals/1981/durga-saptami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/mahashtami",
      "festival": "mahashtami",
      "name": "Mahāṣṭamī",
      "everyday": "Durga Ashtami",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-06",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 22744,
      "anga": {
        "type": "tithi",
        "index": 7,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-10-06T02:44:01+08:00",
          "utc": "1981-10-05T18:44:01Z",
          "ms": 371155441123.88776
        },
        "end": {
          "local": "1981-10-07T04:37:54+08:00",
          "utc": "1981-10-06T20:37:54Z",
          "ms": 371248673709.7348
        },
        "month": {
          "amanta": 6,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-06T02:44:01+08:00",
          "utc": "1981-10-05T18:44:01Z",
          "ms": 371155441123.88776
        },
        "end": {
          "local": "1981-10-07T04:37:54+08:00",
          "utc": "1981-10-06T20:37:54Z",
          "ms": 371248673709.7348
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-10-06",
          "window": {
            "start": {
              "local": "1981-10-06T10:57:15+08:00",
              "utc": "1981-10-06T02:57:15Z",
              "ms": 371185035110.687
            },
            "end": {
              "local": "1981-10-06T11:45:15+08:00",
              "utc": "1981-10-06T03:45:15Z",
              "ms": 371187915110.687
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-10-07",
          "window": {
            "start": {
              "local": "1981-10-07T10:56:58+08:00",
              "utc": "1981-10-07T02:56:58Z",
              "ms": 371271417743.2094
            },
            "end": {
              "local": "1981-10-07T11:44:58+08:00",
              "utc": "1981-10-07T03:44:58Z",
              "ms": 371274297743.2094
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 02:44 on Tue 6 Oct to 04:38 on Wed 7 Oct.",
          "fact": "1981-10-05T18:44:01Z → 1981-10-06T20:37:54Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:57–11:45 on the 6th, 10:57–11:45 on the 7th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be present during madhyāhna. It covers 48 of 48 minutes on the 6th and 0 of 48 on the 7th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 22744 s"
        },
        {
          "step": "ruling",
          "text": "Mahāṣṭamī, Harbin, 1981: Tuesday 6 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "mahashtami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 8 Mahastami (paraviddha)"
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-06",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-06",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Mahāṣṭamī (Durga Ashtami) 1981 falls on Tuesday 6 October. Aṣṭamī runs from 02:44 on Tue 6 Oct to 04:38 on Wed 7 Oct and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/mahashtami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/mahanavami",
      "festival": "mahanavami",
      "name": "Mahānavamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-07",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 18266,
      "anga": {
        "type": "tithi",
        "index": 8,
        "key": "navami",
        "name": "Navamī",
        "start": {
          "local": "1981-10-07T04:37:54+08:00",
          "utc": "1981-10-06T20:37:54Z",
          "ms": 371248673709.7348
        },
        "end": {
          "local": "1981-10-08T05:52:15+08:00",
          "utc": "1981-10-07T21:52:15Z",
          "ms": 371339534945.2302
        },
        "month": {
          "amanta": 6,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-07T04:37:54+08:00",
          "utc": "1981-10-06T20:37:54Z",
          "ms": 371248673709.7348
        },
        "end": {
          "local": "1981-10-08T05:52:15+08:00",
          "utc": "1981-10-07T21:52:15Z",
          "ms": 371339534945.2302
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-10-07",
          "window": {
            "start": {
              "local": "1981-10-07T10:56:58+08:00",
              "utc": "1981-10-07T02:56:58Z",
              "ms": 371271417743.2094
            },
            "end": {
              "local": "1981-10-07T11:44:58+08:00",
              "utc": "1981-10-07T03:44:58Z",
              "ms": 371274297743.2094
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-10-08",
          "window": {
            "start": {
              "local": "1981-10-08T10:56:41+08:00",
              "utc": "1981-10-08T02:56:41Z",
              "ms": 371357800766.23096
            },
            "end": {
              "local": "1981-10-08T11:44:41+08:00",
              "utc": "1981-10-08T03:44:41Z",
              "ms": 371360680766.23096
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Navamī runs from 04:38 on Wed 7 Oct to 05:52 on Thu 8 Oct.",
          "fact": "1981-10-06T20:37:54Z → 1981-10-07T21:52:15Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:57–11:45 on the 7th, 10:57–11:45 on the 8th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Navamī must be present during madhyāhna. It covers 48 of 48 minutes on the 7th and 0 of 48 on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 18266 s"
        },
        {
          "step": "ruling",
          "text": "Mahānavamī, Harbin, 1981: Wednesday 7 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "mahanavami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 9 Mahanavami (purvaviddha) (In Bengal it is observed as paraviddha covering one muhurta from sunrise)."
          }
        ],
        "not_evaluated": "The Bengal reading (paraviddha, one muhūrta from sunrise) is not applied.",
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-07",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-07",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Mahānavamī 1981 falls on Wednesday 7 October. Navamī runs from 04:38 on Wed 7 Oct to 05:52 on Thu 8 Oct and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/mahanavami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vijaya-dashami",
      "festival": "vijaya-dashami",
      "name": "Vijayā Daśamī",
      "everyday": "Dussehra",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-08",
      "confidence": "boundary",
      "boundary_reasons": [
        "tie-break-unstated"
      ],
      "boundary_margin_s": 2222,
      "anga": {
        "type": "tithi",
        "index": 9,
        "key": "dashami",
        "name": "Daśamī",
        "start": {
          "local": "1981-10-08T05:52:15+08:00",
          "utc": "1981-10-07T21:52:15Z",
          "ms": 371339534945.2302
        },
        "end": {
          "local": "1981-10-09T06:18:34+08:00",
          "utc": "1981-10-08T22:18:34Z",
          "ms": 371427514378.2704
        },
        "month": {
          "amanta": 6,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "conjunction",
        "start": {
          "local": "1981-10-08T07:53:45+08:00",
          "utc": "1981-10-07T23:53:45Z",
          "ms": 371346825311.46515
        },
        "end": {
          "local": "1981-10-09T06:18:34+08:00",
          "utc": "1981-10-08T22:18:34Z",
          "ms": 371427514378.2704
        },
        "nakshatra": {
          "type": "nakshatra",
          "index": 21,
          "key": "shravana",
          "name": "Śravaṇa",
          "start": {
            "local": "1981-10-08T07:53:45+08:00",
            "utc": "1981-10-07T23:53:45Z",
            "ms": 371346825311.46515
          },
          "end": {
            "local": "1981-10-09T08:52:30+08:00",
            "utc": "1981-10-09T00:52:30Z",
            "ms": 371436750168.04706
          }
        }
      },
      "kaala": "daytime",
      "days": [
        {
          "local_date": "1981-10-08",
          "window": {
            "start": {
              "local": "1981-10-08T05:40:14+08:00",
              "utc": "1981-10-07T21:40:14Z",
              "ms": 371338814295.7582
            },
            "end": {
              "local": "1981-10-08T17:01:07+08:00",
              "utc": "1981-10-08T09:01:07Z",
              "ms": 371379667236.7038
            }
          },
          "covered_min": 547,
          "window_min": 681,
          "qualifies": true
        },
        {
          "local_date": "1981-10-09",
          "window": {
            "start": {
              "local": "1981-10-09T05:41:33+08:00",
              "utc": "1981-10-08T21:41:33Z",
              "ms": 371425292707.6284
            },
            "end": {
              "local": "1981-10-09T16:59:16+08:00",
              "utc": "1981-10-09T08:59:16Z",
              "ms": 371465955691.9288
            }
          },
          "covered_min": 37,
          "window_min": 678,
          "qualifies": true
        }
      ],
      "decided_by": "greater-coverage",
      "explanation": [
        {
          "step": "anga",
          "text": "Daśamī runs from 05:52 on Thu 8 Oct to 06:19 on Fri 9 Oct, and Śravaṇa from 07:54 on Thu 8 Oct to 08:53 on Fri 9 Oct. They are together from 07:54 on Thu 8 Oct to 06:19 on Fri 9 Oct.",
          "fact": "1981-10-07T23:53:45Z → 1981-10-08T22:18:34Z"
        },
        {
          "step": "kaala",
          "text": "The day time is sunrise to sunset: 05:40–17:01 on the 8th, 05:42–16:59 on the 9th.",
          "fact": "daytime: sunrise-to-sunset · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Where Daśamī touches Śravaṇa in the day time, that day is taken. Together they cover 547 of 681 minutes on the 8th and 37 of 678 on the 9th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Both days qualify and the rule marks neither. The one covered longer is ruled, as a boundary.",
          "fact": "priority: unstated → greater-coverage · margin 2222 s"
        },
        {
          "step": "ruling",
          "text": "Vijayā Daśamī, Harbin, 1981: Thursday 8 October.",
          "fact": "confidence: boundary (tie-break-unstated)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vijaya-dashami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 10 Vijaya dasami (In Bengal it is observed as paraviddha, covering one muhurta from sunrise. In other places, if it touches Sravana naksatra in the day time it is observed on that day), Sarasvati visarjana (to be observed in naksatra Sravana), Dasahara."
          }
        ],
        "not_evaluated": "The Bengal reading (paraviddha, one muhūrta from sunrise) is not applied.",
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day",
        "conjunction": {
          "nakshatra": "Śravaṇa",
          "kaala": "daytime"
        }
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-08",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-08",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Vijayā Daśamī (Dussehra) 1981 falls on Thursday 8 October. Daśamī runs from 05:52 on Thu 8 Oct to 06:19 on Fri 9 Oct and is with Śravaṇa in the day time that day, for 547 minutes. They are together in the day time on the next day too, for 37 minutes; the rule does not say which to take, and the day they share longer is ruled: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vijaya-dashami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-10-10",
      "festival": "ekadashi",
      "name": "Pāśāṅkuśā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-10",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 619,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-10-09T06:18:34+08:00",
          "utc": "1981-10-08T22:18:34Z",
          "ms": 371427514378.2704
        },
        "end": {
          "local": "1981-10-10T05:53:11+08:00",
          "utc": "1981-10-09T21:53:11Z",
          "ms": 371512390529.68317
        },
        "month": {
          "amanta": 6,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-09T06:18:34+08:00",
          "utc": "1981-10-08T22:18:34Z",
          "ms": 371427514378.2704
        },
        "end": {
          "local": "1981-10-10T05:53:11+08:00",
          "utc": "1981-10-09T21:53:11Z",
          "ms": 371512390529.68317
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-10-09",
          "window": {
            "start": {
              "local": "1981-10-09T05:41:33+08:00",
              "utc": "1981-10-08T21:41:33Z",
              "ms": 371425292707.6284
            },
            "end": {
              "local": "1981-10-09T05:41:33+08:00",
              "utc": "1981-10-08T21:41:33Z",
              "ms": 371425292707.6284
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-10-10",
          "window": {
            "start": {
              "local": "1981-10-10T05:42:51+08:00",
              "utc": "1981-10-09T21:42:51Z",
              "ms": 371511771385.8
            },
            "end": {
              "local": "1981-10-10T05:42:51+08:00",
              "utc": "1981-10-09T21:42:51Z",
              "ms": 371511771385.8
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 06:19 on Fri 9 Oct to 05:53 on Sat 10 Oct.",
          "fact": "1981-10-08T22:18:34Z → 1981-10-09T21:53:11Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 05:42 on the 9th and 05:43 on the 10th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 9th and is on the 10th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 619 s"
        },
        {
          "step": "ruling",
          "text": "Pāśāṅkuśā Ekādaśī, Harbin, 1981: Saturday 10 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-10",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-10",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Pāśāṅkuśā Ekādaśī 1981 falls on Saturday 10 October. Ekādaśī runs from 06:19 on Fri 9 Oct to 05:53 on Sat 10 Oct and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-10-10",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-10-11",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 28638,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-10-11T04:37:08+08:00",
          "utc": "1981-10-10T20:37:08Z",
          "ms": 371594228219.20056
        },
        "end": {
          "local": "1981-10-12T02:35:32+08:00",
          "utc": "1981-10-11T18:35:32Z",
          "ms": 371673332078.81757
        },
        "month": {
          "amanta": 6,
          "purnimanta": 6,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Āśvina"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-11T04:37:08+08:00",
          "utc": "1981-10-10T20:37:08Z",
          "ms": 371594228219.20056
        },
        "end": {
          "local": "1981-10-12T02:35:32+08:00",
          "utc": "1981-10-11T18:35:32Z",
          "ms": 371673332078.81757
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-10-10",
          "window": {
            "start": {
              "local": "1981-10-10T16:57:25+08:00",
              "utc": "1981-10-10T08:57:25Z",
              "ms": 371552244743.0687
            },
            "end": {
              "local": "1981-10-10T18:39:39+08:00",
              "utc": "1981-10-10T10:39:39Z",
              "ms": 371558378822.3138
            }
          },
          "covered_min": 0,
          "window_min": 102,
          "qualifies": false
        },
        {
          "local_date": "1981-10-11",
          "window": {
            "start": {
              "local": "1981-10-11T16:55:34+08:00",
              "utc": "1981-10-11T08:55:34Z",
              "ms": 371638534425.4793
            },
            "end": {
              "local": "1981-10-11T18:38:14+08:00",
              "utc": "1981-10-11T10:38:14Z",
              "ms": 371644693778.14343
            }
          },
          "covered_min": 103,
          "window_min": 103,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 04:37 on Sun 11 Oct to 02:36 on Mon 12 Oct.",
          "fact": "1981-10-10T20:37:08Z → 1981-10-11T18:35:32Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:57–18:40 on the 10th, 16:56–18:38 on the 11th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 102 minutes on the 10th and 103 of 103 on the 11th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 28638 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Sunday 11 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Sunday 11 October. Trayodaśī runs from 04:37 on Sun 11 Oct to 02:36 on Mon 12 Oct and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-10-11",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/karaka-chaturthi",
      "festival": "karaka-chaturthi",
      "name": "Karaka Caturthī",
      "everyday": "Karwa Chauth",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 30289,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-10-16T10:29:51+08:00",
          "utc": "1981-10-16T02:29:51Z",
          "ms": 372047390558.7802
        },
        "end": {
          "local": "1981-10-17T07:18:21+08:00",
          "utc": "1981-10-16T23:18:21Z",
          "ms": 372122301165.8827
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-16T10:29:51+08:00",
          "utc": "1981-10-16T02:29:51Z",
          "ms": 372047390558.7802
        },
        "end": {
          "local": "1981-10-17T07:18:21+08:00",
          "utc": "1981-10-16T23:18:21Z",
          "ms": 372122301165.8827
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-10-16",
          "window": {
            "start": {
              "local": "1981-10-16T18:54:40+08:00",
              "utc": "1981-10-16T10:54:40Z",
              "ms": 372077679838.7579
            },
            "end": {
              "local": "1981-10-16T18:54:40+08:00",
              "utc": "1981-10-16T10:54:40Z",
              "ms": 372077679838.7579
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-10-17",
          "window": {
            "start": {
              "local": "1981-10-17T19:39:15+08:00",
              "utc": "1981-10-17T11:39:15Z",
              "ms": 372166755463.6265
            },
            "end": {
              "local": "1981-10-17T19:39:15+08:00",
              "utc": "1981-10-17T11:39:15Z",
              "ms": 372166755463.6265
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 10:30 on Fri 16 Oct to 07:18 on Sat 17 Oct.",
          "fact": "1981-10-16T02:29:51Z → 1981-10-16T23:18:21Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 18:55 on the 16th and 19:39 on the 17th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is on the 16th and is not on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 30289 s"
        },
        {
          "step": "ruling",
          "text": "Karaka Caturthī, Harbin, 1981: Friday 16 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "karaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 4 Karaka caturthi (current at moon-rise, if occurs on two successive days, it is to be observed on the first day)"
          }
        ],
        "kaala": "moonrise",
        "priority": "purvaviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Karaka Caturthī (Karwa Chauth) 1981 falls on Friday 16 October. Caturthī runs from 10:30 on Fri 16 Oct to 07:18 on Sat 17 Oct and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/karaka-chaturthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-10-16",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-16",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 30289,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-10-16T10:29:51+08:00",
          "utc": "1981-10-16T02:29:51Z",
          "ms": 372047390558.7802
        },
        "end": {
          "local": "1981-10-17T07:18:21+08:00",
          "utc": "1981-10-16T23:18:21Z",
          "ms": 372122301165.8827
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-16T10:29:51+08:00",
          "utc": "1981-10-16T02:29:51Z",
          "ms": 372047390558.7802
        },
        "end": {
          "local": "1981-10-17T07:18:21+08:00",
          "utc": "1981-10-16T23:18:21Z",
          "ms": 372122301165.8827
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-10-16",
          "window": {
            "start": {
              "local": "1981-10-16T18:54:40+08:00",
              "utc": "1981-10-16T10:54:40Z",
              "ms": 372077679838.7579
            },
            "end": {
              "local": "1981-10-16T18:54:40+08:00",
              "utc": "1981-10-16T10:54:40Z",
              "ms": 372077679838.7579
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-10-17",
          "window": {
            "start": {
              "local": "1981-10-17T19:39:15+08:00",
              "utc": "1981-10-17T11:39:15Z",
              "ms": 372166755463.6265
            },
            "end": {
              "local": "1981-10-17T19:39:15+08:00",
              "utc": "1981-10-17T11:39:15Z",
              "ms": 372166755463.6265
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 10:30 on Fri 16 Oct to 07:18 on Sat 17 Oct.",
          "fact": "1981-10-16T02:29:51Z → 1981-10-16T23:18:21Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 18:55 on the 16th and 19:39 on the 17th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is on the 16th and is not on the 17th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 30289 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Friday 16 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-16",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-16",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Friday 16 October. Caturthī runs from 10:30 on Fri 16 Oct to 07:18 on Sat 17 Oct and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-10-16",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ahoyi-ashtami",
      "festival": "ahoyi-ashtami",
      "name": "Ahoyī Aṣṭamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-20",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2094,
      "anga": {
        "type": "tithi",
        "index": 22,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-10-20T00:21:14+08:00",
          "utc": "1981-10-19T16:21:14Z",
          "ms": 372356474335.9135
        },
        "end": {
          "local": "1981-10-20T23:08:27+08:00",
          "utc": "1981-10-20T15:08:27Z",
          "ms": 372438506544.0732
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-20T00:21:14+08:00",
          "utc": "1981-10-19T16:21:14Z",
          "ms": 372356474335.9135
        },
        "end": {
          "local": "1981-10-20T23:08:27+08:00",
          "utc": "1981-10-20T15:08:27Z",
          "ms": 372438506544.0732
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-10-19",
          "window": {
            "start": {
              "local": "1981-10-19T21:29:46+08:00",
              "utc": "1981-10-19T13:29:46Z",
              "ms": 372346185804.6442
            },
            "end": {
              "local": "1981-10-19T21:29:46+08:00",
              "utc": "1981-10-19T13:29:46Z",
              "ms": 372346185804.6442
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-10-20",
          "window": {
            "start": {
              "local": "1981-10-20T22:33:32+08:00",
              "utc": "1981-10-20T14:33:32Z",
              "ms": 372436412186.6205
            },
            "end": {
              "local": "1981-10-20T22:33:32+08:00",
              "utc": "1981-10-20T14:33:32Z",
              "ms": 372436412186.6205
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 00:21 on Tue 20 Oct to 23:08 on Tue 20 Oct.",
          "fact": "1981-10-19T16:21:14Z → 1981-10-20T15:08:27Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 21:30 on the 19th and 22:34 on the 20th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be current at moonrise. It is not on the 19th and is on the 20th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 2094 s"
        },
        {
          "step": "ruling",
          "text": "Ahoyī Aṣṭamī, Harbin, 1981: Tuesday 20 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ahoyi-ashtami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 8 Ahoyi astami (Gujerat) (current at moonrise), Karastami (Maharashtra). If occurs on two successive days, it is to be observed on the second day."
          }
        ],
        "kaala": "moonrise",
        "priority": "paraviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-20",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-20",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Ahoyī Aṣṭamī 1981 falls on Tuesday 20 October. Aṣṭamī runs from 00:21 on Tue 20 Oct to 23:08 on Tue 20 Oct and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ahoyi-ashtami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-10-23",
      "festival": "ekadashi",
      "name": "Ramā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-23",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 26112,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-10-22T22:23:42+08:00",
          "utc": "1981-10-22T14:23:42Z",
          "ms": 372608621868.8996
        },
        "end": {
          "local": "1981-10-23T22:46:33+08:00",
          "utc": "1981-10-23T14:46:33Z",
          "ms": 372696392519.1503
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-22T22:23:42+08:00",
          "utc": "1981-10-22T14:23:42Z",
          "ms": 372608621868.8996
        },
        "end": {
          "local": "1981-10-23T22:46:33+08:00",
          "utc": "1981-10-23T14:46:33Z",
          "ms": 372696392519.1503
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-10-23",
          "window": {
            "start": {
              "local": "1981-10-23T06:00:22+08:00",
              "utc": "1981-10-22T22:00:22Z",
              "ms": 372636021828.64905
            },
            "end": {
              "local": "1981-10-23T06:00:22+08:00",
              "utc": "1981-10-22T22:00:22Z",
              "ms": 372636021828.64905
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-10-24",
          "window": {
            "start": {
              "local": "1981-10-24T06:01:45+08:00",
              "utc": "1981-10-23T22:01:45Z",
              "ms": 372722504851.2973
            },
            "end": {
              "local": "1981-10-24T06:01:45+08:00",
              "utc": "1981-10-23T22:01:45Z",
              "ms": 372722504851.2973
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 22:24 on Thu 22 Oct to 22:47 on Fri 23 Oct.",
          "fact": "1981-10-22T14:23:42Z → 1981-10-23T14:46:33Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 06:00 on the 23rd and 06:02 on the 24th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 23rd and is not on the 24th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 26112 s"
        },
        {
          "step": "ruling",
          "text": "Ramā Ekādaśī, Harbin, 1981: Friday 23 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-23",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-23",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Ramā Ekādaśī 1981 falls on Friday 23 October. Ekādaśī runs from 22:24 on Thu 22 Oct to 22:47 on Fri 23 Oct and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-10-23",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/govatsa-dvadashi",
      "festival": "govatsa-dvadashi",
      "name": "Govatsa Dvādaśī",
      "everyday": "Vasu Baras",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-24",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 15862,
      "anga": {
        "type": "tithi",
        "index": 26,
        "key": "dvadashi",
        "name": "Dvādaśī",
        "start": {
          "local": "1981-10-23T22:46:33+08:00",
          "utc": "1981-10-23T14:46:33Z",
          "ms": 372696392519.1503
        },
        "end": {
          "local": "1981-10-24T23:35:17+08:00",
          "utc": "1981-10-24T15:35:17Z",
          "ms": 372785717161.5931
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-23T22:46:33+08:00",
          "utc": "1981-10-23T14:46:33Z",
          "ms": 372696392519.1503
        },
        "end": {
          "local": "1981-10-24T23:35:17+08:00",
          "utc": "1981-10-24T15:35:17Z",
          "ms": 372785717161.5931
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-10-23",
          "window": {
            "start": {
              "local": "1981-10-23T16:34:33+08:00",
              "utc": "1981-10-23T08:34:33Z",
              "ms": 372674073216.1879
            },
            "end": {
              "local": "1981-10-23T18:22:11+08:00",
              "utc": "1981-10-23T10:22:11Z",
              "ms": 372680530767.5358
            }
          },
          "covered_min": 0,
          "window_min": 108,
          "qualifies": false
        },
        {
          "local_date": "1981-10-24",
          "window": {
            "start": {
              "local": "1981-10-24T16:32:54+08:00",
              "utc": "1981-10-24T08:32:54Z",
              "ms": 372760374457.2418
            },
            "end": {
              "local": "1981-10-24T18:20:56+08:00",
              "utc": "1981-10-24T10:20:56Z",
              "ms": 372766856284.347
            }
          },
          "covered_min": 108,
          "window_min": 108,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvādaśī runs from 22:47 on Fri 23 Oct to 23:35 on Sat 24 Oct.",
          "fact": "1981-10-23T14:46:33Z → 1981-10-24T15:35:17Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:35–18:22 on the 23rd, 16:33–18:21 on the 24th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvādaśī must be present during pradoṣa. It covers 0 of 108 minutes on the 23rd and 108 of 108 on the 24th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 15862 s"
        },
        {
          "step": "ruling",
          "text": "Govatsa Dvādaśī, Harbin, 1981: Saturday 24 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "govatsa-dvadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 12 Govatsa dvadasi (pradosa vyapini). If occurs on two days, it is to be observed on the first day."
          }
        ],
        "kaala": "pradosha",
        "priority": "purvaviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-24",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-24",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Govatsa Dvādaśī (Vasu Baras) 1981 falls on Saturday 24 October. Dvādaśī runs from 22:47 on Fri 23 Oct to 23:35 on Sat 24 Oct and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/govatsa-dvadashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/yama-dipadana",
      "festival": "yama-dipadana",
      "name": "Yama Dīpadāna",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-25",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 18861,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-10-24T23:35:17+08:00",
          "utc": "1981-10-24T15:35:17Z",
          "ms": 372785717161.5931
        },
        "end": {
          "local": "1981-10-26T00:47:13+08:00",
          "utc": "1981-10-25T16:47:13Z",
          "ms": 372876432923.1547
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-24T23:35:17+08:00",
          "utc": "1981-10-24T15:35:17Z",
          "ms": 372785717161.5931
        },
        "end": {
          "local": "1981-10-26T00:47:13+08:00",
          "utc": "1981-10-25T16:47:13Z",
          "ms": 372876432923.1547
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-10-24",
          "window": {
            "start": {
              "local": "1981-10-24T16:32:54+08:00",
              "utc": "1981-10-24T08:32:54Z",
              "ms": 372760374457.2418
            },
            "end": {
              "local": "1981-10-24T18:20:56+08:00",
              "utc": "1981-10-24T10:20:56Z",
              "ms": 372766856284.347
            }
          },
          "covered_min": 0,
          "window_min": 108,
          "qualifies": false
        },
        {
          "local_date": "1981-10-25",
          "window": {
            "start": {
              "local": "1981-10-25T16:31:17+08:00",
              "utc": "1981-10-25T08:31:17Z",
              "ms": 372846676845.57825
            },
            "end": {
              "local": "1981-10-25T18:19:43+08:00",
              "utc": "1981-10-25T10:19:43Z",
              "ms": 372853182831.8217
            }
          },
          "covered_min": 108,
          "window_min": 108,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 23:35 on Sat 24 Oct to 00:47 on Mon 26 Oct.",
          "fact": "1981-10-24T15:35:17Z → 1981-10-25T16:47:13Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:33–18:21 on the 24th, 16:31–18:20 on the 25th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 108 minutes on the 24th and 108 of 108 on the 25th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 18861 s"
        },
        {
          "step": "ruling",
          "text": "Yama Dīpadāna, Harbin, 1981: Sunday 25 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "yama-dipadana",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 13 Yama dipadana (pradosa)."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-25",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-25",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Yama Dīpadāna 1981 falls on Sunday 25 October. Trayodaśī runs from 23:35 on Sat 24 Oct to 00:47 on Mon 26 Oct and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/yama-dipadana",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-10-25",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-25",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 18861,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-10-24T23:35:17+08:00",
          "utc": "1981-10-24T15:35:17Z",
          "ms": 372785717161.5931
        },
        "end": {
          "local": "1981-10-26T00:47:13+08:00",
          "utc": "1981-10-25T16:47:13Z",
          "ms": 372876432923.1547
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-24T23:35:17+08:00",
          "utc": "1981-10-24T15:35:17Z",
          "ms": 372785717161.5931
        },
        "end": {
          "local": "1981-10-26T00:47:13+08:00",
          "utc": "1981-10-25T16:47:13Z",
          "ms": 372876432923.1547
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-10-24",
          "window": {
            "start": {
              "local": "1981-10-24T16:32:54+08:00",
              "utc": "1981-10-24T08:32:54Z",
              "ms": 372760374457.2418
            },
            "end": {
              "local": "1981-10-24T18:20:56+08:00",
              "utc": "1981-10-24T10:20:56Z",
              "ms": 372766856284.347
            }
          },
          "covered_min": 0,
          "window_min": 108,
          "qualifies": false
        },
        {
          "local_date": "1981-10-25",
          "window": {
            "start": {
              "local": "1981-10-25T16:31:17+08:00",
              "utc": "1981-10-25T08:31:17Z",
              "ms": 372846676845.57825
            },
            "end": {
              "local": "1981-10-25T18:19:43+08:00",
              "utc": "1981-10-25T10:19:43Z",
              "ms": 372853182831.8217
            }
          },
          "covered_min": 108,
          "window_min": 108,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 23:35 on Sat 24 Oct to 00:47 on Mon 26 Oct.",
          "fact": "1981-10-24T15:35:17Z → 1981-10-25T16:47:13Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:33–18:21 on the 24th, 16:31–18:20 on the 25th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 108 minutes on the 24th and 108 of 108 on the 25th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 18861 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Sunday 25 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-25",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-25",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Sunday 25 October. Trayodaśī runs from 23:35 on Sat 24 Oct to 00:47 on Mon 26 Oct and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-10-25",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/naraka-chaturdashi",
      "festival": "naraka-chaturdashi",
      "name": "Naraka Caturdaśī",
      "everyday": "Choti Diwali",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-26",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 7004,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-10-26T00:47:13+08:00",
          "utc": "1981-10-25T16:47:13Z",
          "ms": 372876432923.1547
        },
        "end": {
          "local": "1981-10-27T02:20:22+08:00",
          "utc": "1981-10-26T18:20:22Z",
          "ms": 372968421698.4843
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-26T00:47:13+08:00",
          "utc": "1981-10-25T16:47:13Z",
          "ms": 372876432923.1547
        },
        "end": {
          "local": "1981-10-27T02:20:22+08:00",
          "utc": "1981-10-26T18:20:22Z",
          "ms": 372968421698.4843
        }
      },
      "kaala": "arunodaya",
      "days": [
        {
          "local_date": "1981-10-26",
          "window": {
            "start": {
              "local": "1981-10-26T04:16:06+08:00",
              "utc": "1981-10-25T20:16:06Z",
              "ms": 372888965756.1608
            },
            "end": {
              "local": "1981-10-26T06:04:32+08:00",
              "utc": "1981-10-25T22:04:32Z",
              "ms": 372895471742.4043
            }
          },
          "covered_min": 108,
          "window_min": 108,
          "qualifies": true
        },
        {
          "local_date": "1981-10-27",
          "window": {
            "start": {
              "local": "1981-10-27T04:17:06+08:00",
              "utc": "1981-10-26T20:17:06Z",
              "ms": 372975425558.0982
            },
            "end": {
              "local": "1981-10-27T06:05:56+08:00",
              "utc": "1981-10-26T22:05:56Z",
              "ms": 372981955579.7496
            }
          },
          "covered_min": 0,
          "window_min": 109,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 00:47 on Mon 26 Oct to 02:20 on Tue 27 Oct.",
          "fact": "1981-10-25T16:47:13Z → 1981-10-26T18:20:22Z"
        },
        {
          "step": "kaala",
          "text": "Aruṇodaya is 2 muhūrtas before sunrise: 04:16–06:05 on the 26th, 04:17–06:06 on the 27th.",
          "fact": "arunodaya: prev-night-muhurta-14-15 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during aruṇodaya. It covers 108 of 108 minutes on the 26th and 0 of 109 on the 27th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one dawn qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 7004 s"
        },
        {
          "step": "ruling",
          "text": "Naraka Caturdaśī, Harbin, 1981: Monday 26 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "naraka-chaturdashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 14 Naraka caturdasi (covering a period of 4 ghatikas before sunrise, if occurs on two successive days, it is to be observed on the first day)"
          }
        ],
        "kaala": "arunodaya",
        "priority": "purvaviddha",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-26",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-26",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Naraka Caturdaśī (Choti Diwali) 1981 falls on Monday 26 October. Caturdaśī runs from 00:47 on Mon 26 Oct to 02:20 on Tue 27 Oct and covers all of aruṇodaya that dawn.",
      "cite": "https://ahargana.org/harbin/festivals/1981/naraka-chaturdashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-10-26",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-26",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 3919,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-10-26T00:47:13+08:00",
          "utc": "1981-10-25T16:47:13Z",
          "ms": 372876432923.1547
        },
        "end": {
          "local": "1981-10-27T02:20:22+08:00",
          "utc": "1981-10-26T18:20:22Z",
          "ms": 372968421698.4843
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-26T00:47:13+08:00",
          "utc": "1981-10-25T16:47:13Z",
          "ms": 372876432923.1547
        },
        "end": {
          "local": "1981-10-27T02:20:22+08:00",
          "utc": "1981-10-26T18:20:22Z",
          "ms": 372968421698.4843
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-10-25",
          "window": {
            "start": {
              "local": "1981-10-25T22:53:54+08:00",
              "utc": "1981-10-25T14:53:54Z",
              "ms": 372869634293.9913
            },
            "end": {
              "local": "1981-10-25T23:41:54+08:00",
              "utc": "1981-10-25T15:41:54Z",
              "ms": 372872514293.9913
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-10-26",
          "window": {
            "start": {
              "local": "1981-10-26T22:53:48+08:00",
              "utc": "1981-10-26T14:53:48Z",
              "ms": 372956027998.55695
            },
            "end": {
              "local": "1981-10-26T23:41:48+08:00",
              "utc": "1981-10-26T15:41:48Z",
              "ms": 372958907998.55695
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 00:47 on Mon 26 Oct to 02:20 on Tue 27 Oct.",
          "fact": "1981-10-25T16:47:13Z → 1981-10-26T18:20:22Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 22:54–23:42 on the 25th, 22:54–23:42 on the 26th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 0 of 48 minutes on the 25th and 48 of 48 on the 26th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 3919 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Monday 26 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-26",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-26",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Monday 26 October. Caturdaśī runs from 00:47 on Mon 26 Oct to 02:20 on Tue 27 Oct and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-10-26",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/diwali-lakshmi-puja",
      "festival": "diwali-lakshmi-puja",
      "name": "Lakṣmī Pūjā",
      "everyday": "Diwali",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-27",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 28911,
      "anga": {
        "type": "tithi",
        "index": 29,
        "key": "amavasya",
        "name": "Amāvasyā",
        "start": {
          "local": "1981-10-27T02:20:22+08:00",
          "utc": "1981-10-26T18:20:22Z",
          "ms": 372968421698.4843
        },
        "end": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-27T02:20:22+08:00",
          "utc": "1981-10-26T18:20:22Z",
          "ms": 372968421698.4843
        },
        "end": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-10-26",
          "window": {
            "start": {
              "local": "1981-10-26T16:29:40+08:00",
              "utc": "1981-10-26T08:29:40Z",
              "ms": 372932980417.3643
            },
            "end": {
              "local": "1981-10-26T18:18:30+08:00",
              "utc": "1981-10-26T10:18:30Z",
              "ms": 372939510439.0157
            }
          },
          "covered_min": 0,
          "window_min": 109,
          "qualifies": false
        },
        {
          "local_date": "1981-10-27",
          "window": {
            "start": {
              "local": "1981-10-27T16:28:05+08:00",
              "utc": "1981-10-27T08:28:05Z",
              "ms": 373019285210.5314
            },
            "end": {
              "local": "1981-10-27T18:17:19+08:00",
              "utc": "1981-10-27T10:17:19Z",
              "ms": 373025839136.4889
            }
          },
          "covered_min": 109,
          "window_min": 109,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Amāvasyā runs from 02:20 on Tue 27 Oct to 04:13 on Wed 28 Oct.",
          "fact": "1981-10-26T18:20:22Z → 1981-10-27T20:13:16Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:30–18:19 on the 26th, 16:28–18:17 on the 27th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Amāvasyā must be present during pradoṣa. It covers 0 of 109 minutes on the 26th and 109 of 109 on the 27th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 28911 s"
        },
        {
          "step": "ruling",
          "text": "Lakṣmī Pūjā, Harbin, 1981: Tuesday 27 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "diwali-lakshmi-puja",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 30 Kali puja (nisithavyapini), Dipavali or Diwali (pradosa), Mahalaksmipuja (pradosa)"
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-27",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-27",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Lakṣmī Pūjā (Diwali) 1981 falls on Tuesday 27 October. Amāvasyā runs from 02:20 on Tue 27 Oct to 04:13 on Wed 28 Oct and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/diwali-lakshmi-puja",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/kali-puja",
      "festival": "kali-puja",
      "name": "Kālī Pūjā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-27",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 9514,
      "anga": {
        "type": "tithi",
        "index": 29,
        "key": "amavasya",
        "name": "Amāvasyā",
        "start": {
          "local": "1981-10-27T02:20:22+08:00",
          "utc": "1981-10-26T18:20:22Z",
          "ms": 372968421698.4843
        },
        "end": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        },
        "month": {
          "amanta": 6,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Āśvina",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-27T02:20:22+08:00",
          "utc": "1981-10-26T18:20:22Z",
          "ms": 372968421698.4843
        },
        "end": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-10-26",
          "window": {
            "start": {
              "local": "1981-10-26T22:53:48+08:00",
              "utc": "1981-10-26T14:53:48Z",
              "ms": 372956027998.55695
            },
            "end": {
              "local": "1981-10-26T23:41:48+08:00",
              "utc": "1981-10-26T15:41:48Z",
              "ms": 372958907998.55695
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-10-27",
          "window": {
            "start": {
              "local": "1981-10-27T22:53:42+08:00",
              "utc": "1981-10-27T14:53:42Z",
              "ms": 373042422432.8721
            },
            "end": {
              "local": "1981-10-27T23:41:42+08:00",
              "utc": "1981-10-27T15:41:42Z",
              "ms": 373045302432.8721
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Amāvasyā runs from 02:20 on Tue 27 Oct to 04:13 on Wed 28 Oct.",
          "fact": "1981-10-26T18:20:22Z → 1981-10-27T20:13:16Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 22:54–23:42 on the 26th, 22:54–23:42 on the 27th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Amāvasyā must be present during niśītha. It covers 0 of 48 minutes on the 26th and 48 of 48 on the 27th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 9514 s"
        },
        {
          "step": "ruling",
          "text": "Kālī Pūjā, Harbin, 1981: Tuesday 27 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "kali-puja",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "K 30 Kali puja (nisithavyapini), Dipavali or Diwali (pradosa), Mahalaksmipuja (pradosa)"
          }
        ],
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-27",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-27",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kālī Pūjā 1981 falls on Tuesday 27 October. Amāvasyā runs from 02:20 on Tue 27 Oct to 04:13 on Wed 28 Oct and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/kali-puja",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/govardhana-puja",
      "festival": "govardhana-puja",
      "name": "Govardhana Pūjā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-28",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 16111,
      "anga": {
        "type": "tithi",
        "index": 0,
        "key": "pratipada",
        "name": "Pratipadā",
        "start": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        },
        "end": {
          "local": "1981-10-29T06:24:20+08:00",
          "utc": "1981-10-28T22:24:20Z",
          "ms": 373155859951.86774
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        },
        "end": {
          "local": "1981-10-29T06:24:20+08:00",
          "utc": "1981-10-28T22:24:20Z",
          "ms": 373155859951.86774
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-10-28",
          "window": {
            "start": {
              "local": "1981-10-28T10:52:55+08:00",
              "utc": "1981-10-28T02:52:55Z",
              "ms": 373085575458.5514
            },
            "end": {
              "local": "1981-10-28T11:40:55+08:00",
              "utc": "1981-10-28T03:40:55Z",
              "ms": 373088455458.5514
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-10-29",
          "window": {
            "start": {
              "local": "1981-10-29T10:52:51+08:00",
              "utc": "1981-10-29T02:52:51Z",
              "ms": 373171971279.25977
            },
            "end": {
              "local": "1981-10-29T11:40:51+08:00",
              "utc": "1981-10-29T03:40:51Z",
              "ms": 373174851279.25977
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pratipadā runs from 04:13 on Wed 28 Oct to 06:24 on Thu 29 Oct.",
          "fact": "1981-10-27T20:13:16Z → 1981-10-28T22:24:20Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:53–11:41 on the 28th, 10:53–11:41 on the 29th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pratipadā must be present during madhyāhna. It covers 48 of 48 minutes on the 28th and 0 of 48 on the 29th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 16111 s"
        },
        {
          "step": "ruling",
          "text": "Govardhana Pūjā, Harbin, 1981: Wednesday 28 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "govardhana-puja",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 1 Govardhana puja, Annakuta [purvaviddha], Balidaityaraja puja (pradosa), Dyuta pratipad (purvahna)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-28",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-28",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Govardhana Pūjā 1981 falls on Wednesday 28 October. Pratipadā runs from 04:13 on Wed 28 Oct to 06:24 on Thu 29 Oct and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/govardhana-puja",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/bali-puja",
      "festival": "bali-puja",
      "name": "Bali Pūjā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-28",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 35757,
      "anga": {
        "type": "tithi",
        "index": 0,
        "key": "pratipada",
        "name": "Pratipadā",
        "start": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        },
        "end": {
          "local": "1981-10-29T06:24:20+08:00",
          "utc": "1981-10-28T22:24:20Z",
          "ms": 373155859951.86774
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        },
        "end": {
          "local": "1981-10-29T06:24:20+08:00",
          "utc": "1981-10-28T22:24:20Z",
          "ms": 373155859951.86774
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-10-27",
          "window": {
            "start": {
              "local": "1981-10-27T16:28:05+08:00",
              "utc": "1981-10-27T08:28:05Z",
              "ms": 373019285210.5314
            },
            "end": {
              "local": "1981-10-27T18:17:19+08:00",
              "utc": "1981-10-27T10:17:19Z",
              "ms": 373025839136.4889
            }
          },
          "covered_min": 0,
          "window_min": 109,
          "qualifies": false
        },
        {
          "local_date": "1981-10-28",
          "window": {
            "start": {
              "local": "1981-10-28T16:26:31+08:00",
              "utc": "1981-10-28T08:26:31Z",
              "ms": 373105591261.88995
            },
            "end": {
              "local": "1981-10-28T18:16:09+08:00",
              "utc": "1981-10-28T10:16:09Z",
              "ms": 373112168953.5437
            }
          },
          "covered_min": 110,
          "window_min": 110,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pratipadā runs from 04:13 on Wed 28 Oct to 06:24 on Thu 29 Oct.",
          "fact": "1981-10-27T20:13:16Z → 1981-10-28T22:24:20Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:28–18:17 on the 27th, 16:27–18:16 on the 28th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pratipadā must be present during pradoṣa. It covers 0 of 109 minutes on the 27th and 110 of 110 on the 28th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 35757 s"
        },
        {
          "step": "ruling",
          "text": "Bali Pūjā, Harbin, 1981: Wednesday 28 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "bali-puja",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 1 Govardhana puja, Annakuta [purvaviddha], Balidaityaraja puja (pradosa), Dyuta pratipad (purvahna)."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-28",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-28",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Bali Pūjā 1981 falls on Wednesday 28 October. Pratipadā runs from 04:13 on Wed 28 Oct to 06:24 on Thu 29 Oct and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/bali-puja",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/dyuta-pratipad",
      "festival": "dyuta-pratipad",
      "name": "Dyūta Pratipad",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-28",
      "confidence": "boundary",
      "boundary_reasons": [
        "tie-break-unstated"
      ],
      "boundary_margin_s": 936,
      "anga": {
        "type": "tithi",
        "index": 0,
        "key": "pratipada",
        "name": "Pratipadā",
        "start": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        },
        "end": {
          "local": "1981-10-29T06:24:20+08:00",
          "utc": "1981-10-28T22:24:20Z",
          "ms": 373155859951.86774
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-28T04:13:16+08:00",
          "utc": "1981-10-27T20:13:16Z",
          "ms": 373061596203.19244
        },
        "end": {
          "local": "1981-10-29T06:24:20+08:00",
          "utc": "1981-10-28T22:24:20Z",
          "ms": 373155859951.86774
        }
      },
      "kaala": "purvahna",
      "days": [
        {
          "local_date": "1981-10-28",
          "window": {
            "start": {
              "local": "1981-10-28T06:07:20+08:00",
              "utc": "1981-10-27T22:07:20Z",
              "ms": 373068439655.21277
            },
            "end": {
              "local": "1981-10-28T09:33:44+08:00",
              "utc": "1981-10-28T01:33:44Z",
              "ms": 373080823524.10516
            }
          },
          "covered_min": 206,
          "window_min": 206,
          "qualifies": true
        },
        {
          "local_date": "1981-10-29",
          "window": {
            "start": {
              "local": "1981-10-29T06:08:44+08:00",
              "utc": "1981-10-28T22:08:44Z",
              "ms": 373154923949.2932
            },
            "end": {
              "local": "1981-10-29T09:34:09+08:00",
              "utc": "1981-10-29T01:34:09Z",
              "ms": 373167248835.9376
            }
          },
          "covered_min": 16,
          "window_min": 205,
          "qualifies": true
        }
      ],
      "decided_by": "greater-coverage",
      "explanation": [
        {
          "step": "anga",
          "text": "Pratipadā runs from 04:13 on Wed 28 Oct to 06:24 on Thu 29 Oct.",
          "fact": "1981-10-27T20:13:16Z → 1981-10-28T22:24:20Z"
        },
        {
          "step": "kaala",
          "text": "Pūrvāhṇa is first 5 of 15 day muhūrtas: 06:07–09:34 on the 28th, 06:09–09:34 on the 29th.",
          "fact": "purvahna: day-muhurta-1-5 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pratipadā must be present during pūrvāhṇa. It covers 206 of 206 minutes on the 28th and 16 of 205 on the 29th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Both forenoons qualify and the rule marks neither. The one covered longer is ruled, as a boundary.",
          "fact": "priority: unstated → greater-coverage · margin 936 s"
        },
        {
          "step": "ruling",
          "text": "Dyūta Pratipad, Harbin, 1981: Wednesday 28 October.",
          "fact": "confidence: boundary (tie-break-unstated)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "dyuta-pratipad",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 1 Govardhana puja, Annakuta [purvaviddha], Balidaityaraja puja (pradosa), Dyuta pratipad (purvahna)."
          }
        ],
        "kaala": "purvahna",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-28",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-28",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Dyūta Pratipad 1981 falls on Wednesday 28 October. Pratipadā runs from 04:13 on Wed 28 Oct to 06:24 on Thu 29 Oct and covers all of pūrvāhṇa that forenoon. It also reaches the next forenoon for 16 minutes; the rule does not say which to take, and the one covered longer is ruled: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/dyuta-pratipad",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/yama-dvitiya",
      "festival": "yama-dvitiya",
      "name": "Yama Dvitīyā",
      "everyday": "Bhai Dooj",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-10-29",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 7318,
      "anga": {
        "type": "tithi",
        "index": 1,
        "key": "dvitiya",
        "name": "Dvitīyā",
        "start": {
          "local": "1981-10-29T06:24:20+08:00",
          "utc": "1981-10-28T22:24:20Z",
          "ms": 373155859951.86774
        },
        "end": {
          "local": "1981-10-30T08:50:50+08:00",
          "utc": "1981-10-30T00:50:50Z",
          "ms": 373251050186.00385
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-29T06:24:20+08:00",
          "utc": "1981-10-28T22:24:20Z",
          "ms": 373155859951.86774
        },
        "end": {
          "local": "1981-10-30T08:50:50+08:00",
          "utc": "1981-10-30T00:50:50Z",
          "ms": 373251050186.00385
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-10-29",
          "window": {
            "start": {
              "local": "1981-10-29T10:52:51+08:00",
              "utc": "1981-10-29T02:52:51Z",
              "ms": 373171971279.25977
            },
            "end": {
              "local": "1981-10-29T11:40:51+08:00",
              "utc": "1981-10-29T03:40:51Z",
              "ms": 373174851279.25977
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-10-30",
          "window": {
            "start": {
              "local": "1981-10-30T10:52:48+08:00",
              "utc": "1981-10-30T02:52:48Z",
              "ms": 373258367865.8804
            },
            "end": {
              "local": "1981-10-30T11:40:48+08:00",
              "utc": "1981-10-30T03:40:48Z",
              "ms": 373261247865.8804
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvitīyā runs from 06:24 on Thu 29 Oct to 08:51 on Fri 30 Oct.",
          "fact": "1981-10-28T22:24:20Z → 1981-10-30T00:50:50Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:53–11:41 on the 29th, 10:53–11:41 on the 30th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvitīyā must be present during madhyāhna. It covers 48 of 48 minutes on the 29th and 0 of 48 on the 30th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 7318 s"
        },
        {
          "step": "ruling",
          "text": "Yama Dvitīyā, Harbin, 1981: Thursday 29 October.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "yama-dvitiya",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 2 Bhratrdvitiya, Yamadvitiya (madhyahna, purvaviddha), Masyadhara (Dwat) puja (Bihar)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-10-29",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-10-29",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Yama Dvitīyā (Bhai Dooj) 1981 falls on Thursday 29 October. Dvitīyā runs from 06:24 on Thu 29 Oct to 08:51 on Fri 30 Oct and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/yama-dvitiya",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/naga-chaturthi",
      "festival": "naga-chaturthi",
      "name": "Nāga Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-01",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 767,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-10-31T11:27:59+08:00",
          "utc": "1981-10-31T03:27:59Z",
          "ms": 373346878507.825
        },
        "end": {
          "local": "1981-11-01T14:08:09+08:00",
          "utc": "1981-11-01T06:08:09Z",
          "ms": 373442889074.2237
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-31T11:27:59+08:00",
          "utc": "1981-10-31T03:27:59Z",
          "ms": 373346878507.825
        },
        "end": {
          "local": "1981-11-01T14:08:09+08:00",
          "utc": "1981-11-01T06:08:09Z",
          "ms": 373442889074.2237
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-10-31",
          "window": {
            "start": {
              "local": "1981-10-31T10:52:45+08:00",
              "utc": "1981-10-31T02:52:45Z",
              "ms": 373344765226.54456
            },
            "end": {
              "local": "1981-10-31T11:40:45+08:00",
              "utc": "1981-10-31T03:40:45Z",
              "ms": 373347645226.54456
            }
          },
          "covered_min": 13,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-11-01",
          "window": {
            "start": {
              "local": "1981-11-01T10:52:43+08:00",
              "utc": "1981-11-01T02:52:43Z",
              "ms": 373431163368.9066
            },
            "end": {
              "local": "1981-11-01T11:40:43+08:00",
              "utc": "1981-11-01T03:40:43Z",
              "ms": 373434043368.9066
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "paraviddha",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 11:28 on Sat 31 Oct to 14:08 on Sun 1 Nov.",
          "fact": "1981-10-31T03:27:59Z → 1981-11-01T06:08:09Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:53–11:41 on the 31st, 10:53–11:41 on the 1st.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 13 of 48 minutes on the 31st and 48 of 48 on the 1st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Both middays qualify. Paraviddhā: the second is taken.",
          "fact": "priority: paraviddha → paraviddha · margin 767 s"
        },
        {
          "step": "ruling",
          "text": "Nāga Caturthī, Harbin, 1981: Sunday 1 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "naga-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 4 Naga caturthi (paraviddha and madhyahnavyapini)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-01",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-01",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Nāga Caturthī 1981 falls on Sunday 1 November. Caturthī runs from 11:28 on Sat 31 Oct to 14:08 on Sun 1 Nov and covers all of madhyāhna that midday. It also reaches the previous midday for 13 minutes; by the rule the second midday is taken.",
      "cite": "https://ahargana.org/harbin/festivals/1981/naga-chaturthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-11-01",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-01",
      "confidence": "boundary",
      "boundary_reasons": [
        "tie-break-unstated"
      ],
      "boundary_margin_s": 767,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-10-31T11:27:59+08:00",
          "utc": "1981-10-31T03:27:59Z",
          "ms": 373346878507.825
        },
        "end": {
          "local": "1981-11-01T14:08:09+08:00",
          "utc": "1981-11-01T06:08:09Z",
          "ms": 373442889074.2237
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-10-31T11:27:59+08:00",
          "utc": "1981-10-31T03:27:59Z",
          "ms": 373346878507.825
        },
        "end": {
          "local": "1981-11-01T14:08:09+08:00",
          "utc": "1981-11-01T06:08:09Z",
          "ms": 373442889074.2237
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-10-31",
          "window": {
            "start": {
              "local": "1981-10-31T10:52:45+08:00",
              "utc": "1981-10-31T02:52:45Z",
              "ms": 373344765226.54456
            },
            "end": {
              "local": "1981-10-31T11:40:45+08:00",
              "utc": "1981-10-31T03:40:45Z",
              "ms": 373347645226.54456
            }
          },
          "covered_min": 13,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-11-01",
          "window": {
            "start": {
              "local": "1981-11-01T10:52:43+08:00",
              "utc": "1981-11-01T02:52:43Z",
              "ms": 373431163368.9066
            },
            "end": {
              "local": "1981-11-01T11:40:43+08:00",
              "utc": "1981-11-01T03:40:43Z",
              "ms": 373434043368.9066
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "greater-coverage",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 11:28 on Sat 31 Oct to 14:08 on Sun 1 Nov.",
          "fact": "1981-10-31T03:27:59Z → 1981-11-01T06:08:09Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:53–11:41 on the 31st, 10:53–11:41 on the 1st.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 13 of 48 minutes on the 31st and 48 of 48 on the 1st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Both middays qualify and the rule marks neither. The one covered longer is ruled, as a boundary.",
          "fact": "priority: unstated → greater-coverage · margin 767 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Sunday 1 November.",
          "fact": "confidence: boundary (tie-break-unstated)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-01",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-01",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Sunday 1 November. Caturthī runs from 11:28 on Sat 31 Oct to 14:08 on Sun 1 Nov and covers all of madhyāhna that midday. It also reaches the previous midday for 13 minutes; the rule does not say which to take, and the one covered longer is ruled: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-11-01",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/surya-shashthi",
      "festival": "surya-shashthi",
      "name": "Sūrya Ṣaṣṭhī",
      "everyday": "Chhath",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-03",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 18014,
      "anga": {
        "type": "tithi",
        "index": 5,
        "key": "shashthi",
        "name": "Ṣaṣṭhī",
        "start": {
          "local": "1981-11-02T16:40:56+08:00",
          "utc": "1981-11-02T08:40:56Z",
          "ms": 373538456005.62634
        },
        "end": {
          "local": "1981-11-03T18:53:55+08:00",
          "utc": "1981-11-03T10:53:55Z",
          "ms": 373632834771.22253
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-02T16:40:56+08:00",
          "utc": "1981-11-02T08:40:56Z",
          "ms": 373538456005.62634
        },
        "end": {
          "local": "1981-11-03T18:53:55+08:00",
          "utc": "1981-11-03T10:53:55Z",
          "ms": 373632834771.22253
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-11-02",
          "window": {
            "start": {
              "local": "1981-11-02T10:52:42+08:00",
              "utc": "1981-11-02T02:52:42Z",
              "ms": 373517562300.1255
            },
            "end": {
              "local": "1981-11-02T11:40:42+08:00",
              "utc": "1981-11-02T03:40:42Z",
              "ms": 373520442300.1255
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-11-03",
          "window": {
            "start": {
              "local": "1981-11-03T10:52:42+08:00",
              "utc": "1981-11-03T02:52:42Z",
              "ms": 373603962027.1521
            },
            "end": {
              "local": "1981-11-03T11:40:42+08:00",
              "utc": "1981-11-03T03:40:42Z",
              "ms": 373606842027.1521
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ṣaṣṭhī runs from 16:41 on Mon 2 Nov to 18:54 on Tue 3 Nov.",
          "fact": "1981-11-02T08:40:56Z → 1981-11-03T10:53:55Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:53–11:41 on the 2nd, 10:53–11:41 on the 3rd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ṣaṣṭhī must be present during madhyāhna. It covers 0 of 48 minutes on the 2nd and 48 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 18014 s"
        },
        {
          "step": "ruling",
          "text": "Sūrya Ṣaṣṭhī, Harbin, 1981: Tuesday 3 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "surya-shashthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 6 Nadi sasthi, Skanda sasthi (Madras), Surya sasthi, Chhat (Bihar)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-03",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-03",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Sūrya Ṣaṣṭhī (Chhath) 1981 falls on Tuesday 3 November. Ṣaṣṭhī runs from 16:41 on Mon 2 Nov to 18:54 on Tue 3 Nov and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/surya-shashthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/gopashtami",
      "festival": "gopashtami",
      "name": "Gopāṣṭamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-05",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 32021,
      "anga": {
        "type": "tithi",
        "index": 7,
        "key": "ashtami",
        "name": "Aṣṭamī",
        "start": {
          "local": "1981-11-04T20:34:24+08:00",
          "utc": "1981-11-04T12:34:24Z",
          "ms": 373725263750.8933
        },
        "end": {
          "local": "1981-11-05T21:31:29+08:00",
          "utc": "1981-11-05T13:31:29Z",
          "ms": 373815088626.5321
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-04T20:34:24+08:00",
          "utc": "1981-11-04T12:34:24Z",
          "ms": 373725263750.8933
        },
        "end": {
          "local": "1981-11-05T21:31:29+08:00",
          "utc": "1981-11-05T13:31:29Z",
          "ms": 373815088626.5321
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-11-04",
          "window": {
            "start": {
              "local": "1981-11-04T10:52:43+08:00",
              "utc": "1981-11-04T02:52:43Z",
              "ms": 373690362556.4431
            },
            "end": {
              "local": "1981-11-04T11:40:43+08:00",
              "utc": "1981-11-04T03:40:43Z",
              "ms": 373693242556.4431
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-11-05",
          "window": {
            "start": {
              "local": "1981-11-05T10:52:44+08:00",
              "utc": "1981-11-05T02:52:44Z",
              "ms": 373776763894.1091
            },
            "end": {
              "local": "1981-11-05T11:40:44+08:00",
              "utc": "1981-11-05T03:40:44Z",
              "ms": 373779643894.1091
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Aṣṭamī runs from 20:34 on Wed 4 Nov to 21:31 on Thu 5 Nov.",
          "fact": "1981-11-04T12:34:24Z → 1981-11-05T13:31:29Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:53–11:41 on the 4th, 10:53–11:41 on the 5th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Aṣṭamī must be present during madhyāhna. It covers 0 of 48 minutes on the 4th and 48 of 48 on the 5th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 32021 s"
        },
        {
          "step": "ruling",
          "text": "Gopāṣṭamī, Harbin, 1981: Thursday 5 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "gopashtami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 8 Gopastami, Gosthastami."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-05",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-05",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Gopāṣṭamī 1981 falls on Thursday 5 November. Aṣṭamī runs from 20:34 on Wed 4 Nov to 21:31 on Thu 5 Nov and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/gopashtami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/akshaya-navami",
      "festival": "akshaya-navami",
      "name": "Akṣaya Navamī",
      "everyday": "Amla Navami",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-06",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 31419,
      "anga": {
        "type": "tithi",
        "index": 8,
        "key": "navami",
        "name": "Navamī",
        "start": {
          "local": "1981-11-05T21:31:29+08:00",
          "utc": "1981-11-05T13:31:29Z",
          "ms": 373815088626.5321
        },
        "end": {
          "local": "1981-11-06T21:37:49+08:00",
          "utc": "1981-11-06T13:37:49Z",
          "ms": 373901869303.164
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-05T21:31:29+08:00",
          "utc": "1981-11-05T13:31:29Z",
          "ms": 373815088626.5321
        },
        "end": {
          "local": "1981-11-06T21:37:49+08:00",
          "utc": "1981-11-06T13:37:49Z",
          "ms": 373901869303.164
        }
      },
      "kaala": "purvahna",
      "days": [
        {
          "local_date": "1981-11-06",
          "window": {
            "start": {
              "local": "1981-11-06T06:20:03+08:00",
              "utc": "1981-11-05T22:20:03Z",
              "ms": 373846803326.8738
            },
            "end": {
              "local": "1981-11-06T09:37:52+08:00",
              "utc": "1981-11-06T01:37:52Z",
              "ms": 373858671806.28937
            }
          },
          "covered_min": 198,
          "window_min": 198,
          "qualifies": true
        },
        {
          "local_date": "1981-11-07",
          "window": {
            "start": {
              "local": "1981-11-07T06:21:28+08:00",
              "utc": "1981-11-06T22:21:28Z",
              "ms": 373933288463.4358
            },
            "end": {
              "local": "1981-11-07T09:38:22+08:00",
              "utc": "1981-11-07T01:38:22Z",
              "ms": 373945102166.35114
            }
          },
          "covered_min": 0,
          "window_min": 197,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Navamī runs from 21:31 on Thu 5 Nov to 21:38 on Fri 6 Nov.",
          "fact": "1981-11-05T13:31:29Z → 1981-11-06T13:37:49Z"
        },
        {
          "step": "kaala",
          "text": "Pūrvāhṇa is first 5 of 15 day muhūrtas: 06:20–09:38 on the 6th, 06:21–09:38 on the 7th.",
          "fact": "purvahna: day-muhurta-1-5 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Navamī must be present during pūrvāhṇa. It covers 198 of 198 minutes on the 6th and 0 of 197 on the 7th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one forenoon qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 31419 s"
        },
        {
          "step": "ruling",
          "text": "Akṣaya Navamī, Harbin, 1981: Friday 6 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "akshaya-navami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 9 Aksaya navami (purvahnavyapini), Jagaddhatri puja (Bengal), (udayavyapini one muhurta), Anla navami (Orissa), Durga navami (purvaviddha), Gauri vrata."
          }
        ],
        "kaala": "purvahna",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-06",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-06",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Akṣaya Navamī (Amla Navami) 1981 falls on Friday 6 November. Navamī runs from 21:31 on Thu 5 Nov to 21:38 on Fri 6 Nov and covers all of pūrvāhṇa that forenoon.",
      "cite": "https://ahargana.org/harbin/festivals/1981/akshaya-navami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/durga-navami",
      "festival": "durga-navami",
      "name": "Durgā Navamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-06",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 35445,
      "anga": {
        "type": "tithi",
        "index": 8,
        "key": "navami",
        "name": "Navamī",
        "start": {
          "local": "1981-11-05T21:31:29+08:00",
          "utc": "1981-11-05T13:31:29Z",
          "ms": 373815088626.5321
        },
        "end": {
          "local": "1981-11-06T21:37:49+08:00",
          "utc": "1981-11-06T13:37:49Z",
          "ms": 373901869303.164
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-05T21:31:29+08:00",
          "utc": "1981-11-05T13:31:29Z",
          "ms": 373815088626.5321
        },
        "end": {
          "local": "1981-11-06T21:37:49+08:00",
          "utc": "1981-11-06T13:37:49Z",
          "ms": 373901869303.164
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-11-05",
          "window": {
            "start": {
              "local": "1981-11-05T10:52:44+08:00",
              "utc": "1981-11-05T02:52:44Z",
              "ms": 373776763894.1091
            },
            "end": {
              "local": "1981-11-05T11:40:44+08:00",
              "utc": "1981-11-05T03:40:44Z",
              "ms": 373779643894.1091
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-11-06",
          "window": {
            "start": {
              "local": "1981-11-06T10:52:46+08:00",
              "utc": "1981-11-06T02:52:46Z",
              "ms": 373863166045.9972
            },
            "end": {
              "local": "1981-11-06T11:40:46+08:00",
              "utc": "1981-11-06T03:40:46Z",
              "ms": 373866046045.9972
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Navamī runs from 21:31 on Thu 5 Nov to 21:38 on Fri 6 Nov.",
          "fact": "1981-11-05T13:31:29Z → 1981-11-06T13:37:49Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:53–11:41 on the 5th, 10:53–11:41 on the 6th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Navamī must be present during madhyāhna. It covers 0 of 48 minutes on the 5th and 48 of 48 on the 6th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 35445 s"
        },
        {
          "step": "ruling",
          "text": "Durgā Navamī, Harbin, 1981: Friday 6 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "durga-navami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 9 Aksaya navami (purvahnavyapini), Jagaddhatri puja (Bengal), (udayavyapini one muhurta), Anla navami (Orissa), Durga navami (purvaviddha), Gauri vrata."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-06",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-06",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Durgā Navamī 1981 falls on Friday 6 November. Navamī runs from 21:31 on Thu 5 Nov to 21:38 on Fri 6 Nov and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/durga-navami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-11-08",
      "festival": "ekadashi",
      "name": "Prabodhinī Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-08",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 34336,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-11-07T20:50:38+08:00",
          "utc": "1981-11-07T12:50:38Z",
          "ms": 373985437639.2032
        },
        "end": {
          "local": "1981-11-08T19:11:38+08:00",
          "utc": "1981-11-08T11:11:38Z",
          "ms": 374065898309.86774
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-07T20:50:38+08:00",
          "utc": "1981-11-07T12:50:38Z",
          "ms": 373985437639.2032
        },
        "end": {
          "local": "1981-11-08T19:11:38+08:00",
          "utc": "1981-11-08T11:11:38Z",
          "ms": 374065898309.86774
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-11-08",
          "window": {
            "start": {
              "local": "1981-11-08T06:22:54+08:00",
              "utc": "1981-11-07T22:22:54Z",
              "ms": 374019773544.8636
            },
            "end": {
              "local": "1981-11-08T06:22:54+08:00",
              "utc": "1981-11-07T22:22:54Z",
              "ms": 374019773544.8636
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-11-09",
          "window": {
            "start": {
              "local": "1981-11-09T06:24:19+08:00",
              "utc": "1981-11-08T22:24:19Z",
              "ms": 374106258538.46454
            },
            "end": {
              "local": "1981-11-09T06:24:19+08:00",
              "utc": "1981-11-08T22:24:19Z",
              "ms": 374106258538.46454
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 20:51 on Sat 7 Nov to 19:12 on Sun 8 Nov.",
          "fact": "1981-11-07T12:50:38Z → 1981-11-08T11:11:38Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 06:23 on the 8th and 06:24 on the 9th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 8th and is not on the 9th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 34336 s"
        },
        {
          "step": "ruling",
          "text": "Prabodhinī Ekādaśī, Harbin, 1981: Sunday 8 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-08",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-08",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Prabodhinī Ekādaśī 1981 falls on Sunday 8 November. Ekādaśī runs from 20:51 on Sat 7 Nov to 19:12 on Sun 8 Nov and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-11-08",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-11-09",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-09",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2211,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-11-09T16:46:27+08:00",
          "utc": "1981-11-09T08:46:27Z",
          "ms": 374143587343.6004
        },
        "end": {
          "local": "1981-11-10T13:43:31+08:00",
          "utc": "1981-11-10T05:43:31Z",
          "ms": 374219011447.3523
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-09T16:46:27+08:00",
          "utc": "1981-11-09T08:46:27Z",
          "ms": 374143587343.6004
        },
        "end": {
          "local": "1981-11-10T13:43:31+08:00",
          "utc": "1981-11-10T05:43:31Z",
          "ms": 374219011447.3523
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-11-09",
          "window": {
            "start": {
              "local": "1981-11-09T16:09:36+08:00",
              "utc": "1981-11-09T08:09:36Z",
              "ms": 374141376349.8757
            },
            "end": {
              "local": "1981-11-09T18:03:45+08:00",
              "utc": "1981-11-09T10:03:45Z",
              "ms": 374148225291.4471
            }
          },
          "covered_min": 77,
          "window_min": 114,
          "qualifies": true
        },
        {
          "local_date": "1981-11-10",
          "window": {
            "start": {
              "local": "1981-11-10T16:08:22+08:00",
              "utc": "1981-11-10T08:08:22Z",
              "ms": 374227702409.7065
            },
            "end": {
              "local": "1981-11-10T18:02:53+08:00",
              "utc": "1981-11-10T10:02:53Z",
              "ms": 374234572506.0254
            }
          },
          "covered_min": 0,
          "window_min": 115,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 16:46 on Mon 9 Nov to 13:44 on Tue 10 Nov.",
          "fact": "1981-11-09T08:46:27Z → 1981-11-10T05:43:31Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 16:10–18:04 on the 9th, 16:08–18:03 on the 10th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 77 of 114 minutes on the 9th and 0 of 115 on the 10th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 2211 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Monday 9 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-09",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-09",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Monday 9 November. Trayodaśī runs from 16:46 on Mon 9 Nov to 13:44 on Tue 10 Nov and covers 77 of 114 minutes of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-11-09",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/kartiki-purnima",
      "festival": "kartiki-purnima",
      "name": "Kārtikī Pūrṇimā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2402,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-11-11T10:13:07+08:00",
          "utc": "1981-11-11T02:13:07Z",
          "ms": 374292787116.7033
        },
        "end": {
          "local": "1981-11-12T06:26:29+08:00",
          "utc": "1981-11-11T22:26:29Z",
          "ms": 374365589316.83636
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-11T10:13:07+08:00",
          "utc": "1981-11-11T02:13:07Z",
          "ms": 374292787116.7033
        },
        "end": {
          "local": "1981-11-12T06:26:29+08:00",
          "utc": "1981-11-11T22:26:29Z",
          "ms": 374365589316.83636
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-11-11",
          "window": {
            "start": {
              "local": "1981-11-11T10:53:09+08:00",
              "utc": "1981-11-11T02:53:09Z",
              "ms": 374295189221.11597
            },
            "end": {
              "local": "1981-11-11T11:41:09+08:00",
              "utc": "1981-11-11T03:41:09Z",
              "ms": 374298069221.11597
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-11-12",
          "window": {
            "start": {
              "local": "1981-11-12T10:53:16+08:00",
              "utc": "1981-11-12T02:53:16Z",
              "ms": 374381596381.78986
            },
            "end": {
              "local": "1981-11-12T11:41:16+08:00",
              "utc": "1981-11-12T03:41:16Z",
              "ms": 374384476381.78986
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 10:13 on Wed 11 Nov to 06:26 on Thu 12 Nov.",
          "fact": "1981-11-11T02:13:07Z → 1981-11-11T22:26:29Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:53–11:41 on the 11th, 10:53–11:41 on the 12th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during madhyāhna. It covers 48 of 48 minutes on the 11th and 0 of 48 on the 12th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 2402 s"
        },
        {
          "step": "ruling",
          "text": "Kārtikī Pūrṇimā, Harbin, 1981: Wednesday 11 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "kartiki-purnima",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Rasayatra, (nisithavyapini, i.e. covering a period from 24 minutes before to 24 minutes after midnight. If occurs on two days or does not occur on any day, it is to be observed on the second day), Puskar Fair. Ratha yatra (Jain), Tripurotsava (evening), Kedara vrata (Orissa), Kartiki purnima."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kārtikī Pūrṇimā 1981 falls on Wednesday 11 November. Pūrṇimā runs from 10:13 on Wed 11 Nov to 06:26 on Thu 12 Nov and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/kartiki-purnima",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/rasayatra",
      "festival": "rasayatra",
      "name": "Rāsayātrā",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 24278,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-11-11T10:13:07+08:00",
          "utc": "1981-11-11T02:13:07Z",
          "ms": 374292787116.7033
        },
        "end": {
          "local": "1981-11-12T06:26:29+08:00",
          "utc": "1981-11-11T22:26:29Z",
          "ms": 374365589316.83636
        },
        "month": {
          "amanta": 7,
          "purnimanta": 7,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Kārtika"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-11T10:13:07+08:00",
          "utc": "1981-11-11T02:13:07Z",
          "ms": 374292787116.7033
        },
        "end": {
          "local": "1981-11-12T06:26:29+08:00",
          "utc": "1981-11-11T22:26:29Z",
          "ms": 374365589316.83636
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-11-10",
          "window": {
            "start": {
              "local": "1981-11-10T22:53:45+08:00",
              "utc": "1981-11-10T14:53:45Z",
              "ms": 374252025270.9024
            },
            "end": {
              "local": "1981-11-10T23:41:45+08:00",
              "utc": "1981-11-10T15:41:45Z",
              "ms": 374254905270.9024
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-11-11",
          "window": {
            "start": {
              "local": "1981-11-11T22:53:51+08:00",
              "utc": "1981-11-11T14:53:51Z",
              "ms": 374338431488.72217
            },
            "end": {
              "local": "1981-11-11T23:41:51+08:00",
              "utc": "1981-11-11T15:41:51Z",
              "ms": 374341311488.72217
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 10:13 on Wed 11 Nov to 06:26 on Thu 12 Nov.",
          "fact": "1981-11-11T02:13:07Z → 1981-11-11T22:26:29Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 22:54–23:42 on the 10th, 22:54–23:42 on the 11th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during niśītha. It covers 0 of 48 minutes on the 10th and 48 of 48 on the 11th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 24278 s"
        },
        {
          "step": "ruling",
          "text": "Rāsayātrā, Harbin, 1981: Wednesday 11 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "rasayatra",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Rasayatra, (nisithavyapini, i.e. covering a period from 24 minutes before to 24 minutes after midnight. If occurs on two days or does not occur on any day, it is to be observed on the second day), Puskar Fair. Ratha yatra (Jain), Tripurotsava (evening), Kedara vrata (Orissa), Kartiki purnima."
          }
        ],
        "kaala": "nishita",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Rāsayātrā 1981 falls on Wednesday 11 November. Pūrṇimā runs from 10:13 on Wed 11 Nov to 06:26 on Thu 12 Nov and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/rasayatra",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-11-14",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-14",
      "confidence": "boundary",
      "boundary_reasons": [
        "absent-unstated"
      ],
      "boundary_margin_s": 3901,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-11-14T19:23:14+08:00",
          "utc": "1981-11-14T11:23:14Z",
          "ms": 374584994369.12
        },
        "end": {
          "local": "1981-11-15T16:22:43+08:00",
          "utc": "1981-11-15T08:22:43Z",
          "ms": 374660562791.789
        },
        "month": {
          "amanta": 7,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-14T19:23:14+08:00",
          "utc": "1981-11-14T11:23:14Z",
          "ms": 374584994369.12
        },
        "end": {
          "local": "1981-11-15T16:22:43+08:00",
          "utc": "1981-11-15T08:22:43Z",
          "ms": 374660562791.789
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-11-14",
          "window": {
            "start": {
              "local": "1981-11-14T18:18:13+08:00",
              "utc": "1981-11-14T10:18:13Z",
              "ms": 374581093065.49335
            },
            "end": {
              "local": "1981-11-14T18:18:13+08:00",
              "utc": "1981-11-14T10:18:13Z",
              "ms": 374581093065.49335
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-11-15",
          "window": {
            "start": {
              "local": "1981-11-15T19:16:20+08:00",
              "utc": "1981-11-15T11:16:20Z",
              "ms": 374670980132.34344
            },
            "end": {
              "local": "1981-11-15T19:16:20+08:00",
              "utc": "1981-11-15T11:16:20Z",
              "ms": 374670980132.34344
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "tithi-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 19:23 on Sat 14 Nov to 16:23 on Sun 15 Nov.",
          "fact": "1981-11-14T11:23:14Z → 1981-11-15T08:22:43Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 18:18 on the 14th and 19:16 on the 15th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is not on the 14th and is not on the 15th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Neither moonrise qualifies. The day the tithi falls on is taken.",
          "fact": "priority: unstated → tithi-day · margin 3901 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Saturday 14 November.",
          "fact": "confidence: boundary (absent-unstated)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-14",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-14",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Saturday 14 November. Caturthī runs from 19:23 on Sat 14 Nov to 16:23 on Sun 15 Nov, and is current at moonrise on neither day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-11-14",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-11-22",
      "festival": "ekadashi",
      "name": "Utpannā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-22",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 19680,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-11-21T12:08:59+08:00",
          "utc": "1981-11-21T04:08:59Z",
          "ms": 375163739180.96686
        },
        "end": {
          "local": "1981-11-22T13:37:09+08:00",
          "utc": "1981-11-22T05:37:09Z",
          "ms": 375255428815.07294
        },
        "month": {
          "amanta": 7,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-21T12:08:59+08:00",
          "utc": "1981-11-21T04:08:59Z",
          "ms": 375163739180.96686
        },
        "end": {
          "local": "1981-11-22T13:37:09+08:00",
          "utc": "1981-11-22T05:37:09Z",
          "ms": 375255428815.07294
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-11-21",
          "window": {
            "start": {
              "local": "1981-11-21T06:40:59+08:00",
              "utc": "1981-11-20T22:40:59Z",
              "ms": 375144058699.27313
            },
            "end": {
              "local": "1981-11-21T06:40:59+08:00",
              "utc": "1981-11-20T22:40:59Z",
              "ms": 375144058699.27313
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-11-22",
          "window": {
            "start": {
              "local": "1981-11-22T06:42:19+08:00",
              "utc": "1981-11-21T22:42:19Z",
              "ms": 375230539061.81323
            },
            "end": {
              "local": "1981-11-22T06:42:19+08:00",
              "utc": "1981-11-21T22:42:19Z",
              "ms": 375230539061.81323
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 12:09 on Sat 21 Nov to 13:37 on Sun 22 Nov.",
          "fact": "1981-11-21T04:08:59Z → 1981-11-22T05:37:09Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 06:41 on the 21st and 06:42 on the 22nd.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 21st and is on the 22nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Only one sunrise qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 19680 s"
        },
        {
          "step": "ruling",
          "text": "Utpannā Ekādaśī, Harbin, 1981: Sunday 22 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-22",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-22",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Utpannā Ekādaśī 1981 falls on Sunday 22 November. Ekādaśī runs from 12:09 on Sat 21 Nov to 13:37 on Sun 22 Nov and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-11-22",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-11-23",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-23",
      "confidence": "boundary",
      "boundary_reasons": [
        "tie-break-unstated"
      ],
      "boundary_margin_s": 793,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-11-23T15:29:29+08:00",
          "utc": "1981-11-23T07:29:29Z",
          "ms": 375348569410.1628
        },
        "end": {
          "local": "1981-11-24T17:40:21+08:00",
          "utc": "1981-11-24T09:40:21Z",
          "ms": 375442820577.5106
        },
        "month": {
          "amanta": 7,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-23T15:29:29+08:00",
          "utc": "1981-11-23T07:29:29Z",
          "ms": 375348569410.1628
        },
        "end": {
          "local": "1981-11-24T17:40:21+08:00",
          "utc": "1981-11-24T09:40:21Z",
          "ms": 375442820577.5106
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-11-23",
          "window": {
            "start": {
              "local": "1981-11-23T15:55:25+08:00",
              "utc": "1981-11-23T07:55:25Z",
              "ms": 375350124801.66095
            },
            "end": {
              "local": "1981-11-23T17:54:01+08:00",
              "utc": "1981-11-23T09:54:01Z",
              "ms": 375357241172.54553
            }
          },
          "covered_min": 119,
          "window_min": 119,
          "qualifies": true
        },
        {
          "local_date": "1981-11-24",
          "window": {
            "start": {
              "local": "1981-11-24T15:54:41+08:00",
              "utc": "1981-11-24T07:54:41Z",
              "ms": 375436480568.6104
            },
            "end": {
              "local": "1981-11-24T17:53:33+08:00",
              "utc": "1981-11-24T09:53:33Z",
              "ms": 375443613241.4337
            }
          },
          "covered_min": 106,
          "window_min": 119,
          "qualifies": true
        }
      ],
      "decided_by": "greater-coverage",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 15:29 on Mon 23 Nov to 17:40 on Tue 24 Nov.",
          "fact": "1981-11-23T07:29:29Z → 1981-11-24T09:40:21Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 15:55–17:54 on the 23rd, 15:55–17:54 on the 24th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 119 of 119 minutes on the 23rd and 106 of 119 on the 24th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Both evenings qualify and the rule marks neither. The one covered longer is ruled, as a boundary.",
          "fact": "priority: unstated → greater-coverage · margin 793 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Monday 23 November.",
          "fact": "confidence: boundary (tie-break-unstated)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-23",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-23",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Monday 23 November. Trayodaśī runs from 15:29 on Mon 23 Nov to 17:40 on Tue 24 Nov and covers all of pradoṣa that evening. It also reaches the next evening for 106 minutes; the rule does not say which to take, and the one covered longer is ruled: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-11-23",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-11-24",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-24",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 10320,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-11-24T17:40:21+08:00",
          "utc": "1981-11-24T09:40:21Z",
          "ms": 375442820577.5106
        },
        "end": {
          "local": "1981-11-25T20:04:46+08:00",
          "utc": "1981-11-25T12:04:46Z",
          "ms": 375537885858.6212
        },
        "month": {
          "amanta": 7,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Kārtika",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-24T17:40:21+08:00",
          "utc": "1981-11-24T09:40:21Z",
          "ms": 375442820577.5106
        },
        "end": {
          "local": "1981-11-25T20:04:46+08:00",
          "utc": "1981-11-25T12:04:46Z",
          "ms": 375537885858.6212
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-11-24",
          "window": {
            "start": {
              "local": "1981-11-24T22:56:28+08:00",
              "utc": "1981-11-24T14:56:28Z",
              "ms": 375461788091.69775
            },
            "end": {
              "local": "1981-11-24T23:44:28+08:00",
              "utc": "1981-11-24T15:44:28Z",
              "ms": 375464668091.69775
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-11-25",
          "window": {
            "start": {
              "local": "1981-11-25T22:56:46+08:00",
              "utc": "1981-11-25T14:56:46Z",
              "ms": 375548205742.9508
            },
            "end": {
              "local": "1981-11-25T23:44:46+08:00",
              "utc": "1981-11-25T15:44:46Z",
              "ms": 375551085742.9508
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 17:40 on Tue 24 Nov to 20:05 on Wed 25 Nov.",
          "fact": "1981-11-24T09:40:21Z → 1981-11-25T12:04:46Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 22:56–23:44 on the 24th, 22:57–23:45 on the 25th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 48 of 48 minutes on the 24th and 0 of 48 on the 25th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 10320 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Tuesday 24 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-24",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-24",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Tuesday 24 November. Caturdaśī runs from 17:40 on Tue 24 Nov to 20:05 on Wed 25 Nov and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-11-24",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-11-30",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-11-30",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 8301,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-11-30T06:24:43+08:00",
          "utc": "1981-11-29T22:24:43Z",
          "ms": 375920682799.7265
        },
        "end": {
          "local": "1981-12-01T08:39:50+08:00",
          "utc": "1981-12-01T00:39:50Z",
          "ms": 376015189856.88855
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-11-30T06:24:43+08:00",
          "utc": "1981-11-29T22:24:43Z",
          "ms": 375920682799.7265
        },
        "end": {
          "local": "1981-12-01T08:39:50+08:00",
          "utc": "1981-12-01T00:39:50Z",
          "ms": 376015189856.88855
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-11-30",
          "window": {
            "start": {
              "local": "1981-11-30T10:57:49+08:00",
              "utc": "1981-11-30T02:57:49Z",
              "ms": 375937068834.714
            },
            "end": {
              "local": "1981-11-30T11:45:49+08:00",
              "utc": "1981-11-30T03:45:49Z",
              "ms": 375939948834.714
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-12-01",
          "window": {
            "start": {
              "local": "1981-12-01T10:58:11+08:00",
              "utc": "1981-12-01T02:58:11Z",
              "ms": 376023491246.0074
            },
            "end": {
              "local": "1981-12-01T11:46:11+08:00",
              "utc": "1981-12-01T03:46:11Z",
              "ms": 376026371246.0074
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 06:25 on Mon 30 Nov to 08:40 on Tue 1 Dec.",
          "fact": "1981-11-29T22:24:43Z → 1981-12-01T00:39:50Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:58–11:46 on the 30th, 10:58–11:46 on the 1st.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 48 of 48 minutes on the 30th and 0 of 48 on the 1st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 8301 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Monday 30 November.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-11-30",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-11-30",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Monday 30 November. Caturthī runs from 06:25 on Mon 30 Nov to 08:40 on Tue 1 Dec and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-11-30",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/naga-panchami-margashirsha",
      "festival": "naga-panchami-margashirsha",
      "name": "Nāga Pañcamī (Mārgaśīrṣa)",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-01",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 1691,
      "anga": {
        "type": "tithi",
        "index": 4,
        "key": "panchami",
        "name": "Pañcamī",
        "start": {
          "local": "1981-12-01T08:39:50+08:00",
          "utc": "1981-12-01T00:39:50Z",
          "ms": 376015189856.88855
        },
        "end": {
          "local": "1981-12-02T10:30:23+08:00",
          "utc": "1981-12-02T02:30:23Z",
          "ms": 376108223046.49054
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-01T08:39:50+08:00",
          "utc": "1981-12-01T00:39:50Z",
          "ms": 376015189856.88855
        },
        "end": {
          "local": "1981-12-02T10:30:23+08:00",
          "utc": "1981-12-02T02:30:23Z",
          "ms": 376108223046.49054
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-12-01",
          "window": {
            "start": {
              "local": "1981-12-01T10:58:11+08:00",
              "utc": "1981-12-01T02:58:11Z",
              "ms": 376023491246.0074
            },
            "end": {
              "local": "1981-12-01T11:46:11+08:00",
              "utc": "1981-12-01T03:46:11Z",
              "ms": 376026371246.0074
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-12-02",
          "window": {
            "start": {
              "local": "1981-12-02T10:58:34+08:00",
              "utc": "1981-12-02T02:58:34Z",
              "ms": 376109914297.5862
            },
            "end": {
              "local": "1981-12-02T11:46:34+08:00",
              "utc": "1981-12-02T03:46:34Z",
              "ms": 376112794297.5862
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pañcamī runs from 08:40 on Tue 1 Dec to 10:30 on Wed 2 Dec.",
          "fact": "1981-12-01T00:39:50Z → 1981-12-02T02:30:23Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:58–11:46 on the 1st, 10:59–11:47 on the 2nd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pañcamī must be present during madhyāhna. It covers 48 of 48 minutes on the 1st and 0 of 48 on the 2nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 1691 s"
        },
        {
          "step": "ruling",
          "text": "Nāga Pañcamī (Mārgaśīrṣa), Harbin, 1981: Tuesday 1 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "naga-panchami-margashirsha",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 5 Naga pancami (2nd) (paraviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-01",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-02",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Nāga Pañcamī (Mārgaśīrṣa) 1981 falls on Tuesday 1 December. Pañcamī runs from 08:40 on Tue 1 Dec to 10:30 on Wed 2 Dec and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/naga-panchami-margashirsha",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/skanda-shashthi",
      "festival": "skanda-shashthi",
      "name": "Skanda Ṣaṣṭhī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-02",
      "confidence": "boundary",
      "boundary_reasons": [
        "margin"
      ],
      "boundary_margin_s": 9,
      "anga": {
        "type": "tithi",
        "index": 5,
        "key": "shashthi",
        "name": "Ṣaṣṭhī",
        "start": {
          "local": "1981-12-02T10:30:23+08:00",
          "utc": "1981-12-02T02:30:23Z",
          "ms": 376108223046.49054
        },
        "end": {
          "local": "1981-12-03T11:47:07+08:00",
          "utc": "1981-12-03T03:47:07Z",
          "ms": 376199227304.56415
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-02T10:30:23+08:00",
          "utc": "1981-12-02T02:30:23Z",
          "ms": 376108223046.49054
        },
        "end": {
          "local": "1981-12-03T11:47:07+08:00",
          "utc": "1981-12-03T03:47:07Z",
          "ms": 376199227304.56415
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-12-02",
          "window": {
            "start": {
              "local": "1981-12-02T10:58:34+08:00",
              "utc": "1981-12-02T02:58:34Z",
              "ms": 376109914297.5862
            },
            "end": {
              "local": "1981-12-02T11:46:34+08:00",
              "utc": "1981-12-02T03:46:34Z",
              "ms": 376112794297.5862
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-12-03",
          "window": {
            "start": {
              "local": "1981-12-03T10:58:58+08:00",
              "utc": "1981-12-03T02:58:58Z",
              "ms": 376196337964.99585
            },
            "end": {
              "local": "1981-12-03T11:46:58+08:00",
              "utc": "1981-12-03T03:46:58Z",
              "ms": 376199217964.99585
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "purvaviddha",
      "explanation": [
        {
          "step": "anga",
          "text": "Ṣaṣṭhī runs from 10:30 on Wed 2 Dec to 11:47 on Thu 3 Dec.",
          "fact": "1981-12-02T02:30:23Z → 1981-12-03T03:47:07Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:59–11:47 on the 2nd, 10:59–11:47 on the 3rd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ṣaṣṭhī must be present during madhyāhna. It covers 48 of 48 minutes on the 2nd and 48 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Both middays qualify. Pūrvaviddhā: the first is taken.",
          "fact": "priority: purvaviddha → purvaviddha · margin 9 s < 300 s"
        },
        {
          "step": "ruling",
          "text": "Skanda Ṣaṣṭhī, Harbin, 1981: Wednesday 2 December.",
          "fact": "confidence: boundary (margin)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "skanda-shashthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 6 Campa sasthi (Maharashtra) (paraviddha). (Special when combined with naksatra Satabhisaj, yoga Vyatipata and Sunday), Skanda sasthi (purvaviddha), Guha sasthi"
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-02",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-02",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Skanda Ṣaṣṭhī 1981 falls on Wednesday 2 December. Ṣaṣṭhī runs from 10:30 on Wed 2 Dec to 11:47 on Thu 3 Dec and covers all of madhyāhna that midday. It also reaches the next midday for 48 minutes; by the rule the first midday is taken. It is 0 min 09 s from a threshold: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/skanda-shashthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/champa-shashthi",
      "festival": "champa-shashthi",
      "name": "Campā Ṣaṣṭhī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-03",
      "confidence": "boundary",
      "boundary_reasons": [
        "margin"
      ],
      "boundary_margin_s": 9,
      "anga": {
        "type": "tithi",
        "index": 5,
        "key": "shashthi",
        "name": "Ṣaṣṭhī",
        "start": {
          "local": "1981-12-02T10:30:23+08:00",
          "utc": "1981-12-02T02:30:23Z",
          "ms": 376108223046.49054
        },
        "end": {
          "local": "1981-12-03T11:47:07+08:00",
          "utc": "1981-12-03T03:47:07Z",
          "ms": 376199227304.56415
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-02T10:30:23+08:00",
          "utc": "1981-12-02T02:30:23Z",
          "ms": 376108223046.49054
        },
        "end": {
          "local": "1981-12-03T11:47:07+08:00",
          "utc": "1981-12-03T03:47:07Z",
          "ms": 376199227304.56415
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-12-02",
          "window": {
            "start": {
              "local": "1981-12-02T10:58:34+08:00",
              "utc": "1981-12-02T02:58:34Z",
              "ms": 376109914297.5862
            },
            "end": {
              "local": "1981-12-02T11:46:34+08:00",
              "utc": "1981-12-02T03:46:34Z",
              "ms": 376112794297.5862
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-12-03",
          "window": {
            "start": {
              "local": "1981-12-03T10:58:58+08:00",
              "utc": "1981-12-03T02:58:58Z",
              "ms": 376196337964.99585
            },
            "end": {
              "local": "1981-12-03T11:46:58+08:00",
              "utc": "1981-12-03T03:46:58Z",
              "ms": 376199217964.99585
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "paraviddha",
      "explanation": [
        {
          "step": "anga",
          "text": "Ṣaṣṭhī runs from 10:30 on Wed 2 Dec to 11:47 on Thu 3 Dec.",
          "fact": "1981-12-02T02:30:23Z → 1981-12-03T03:47:07Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:59–11:47 on the 2nd, 10:59–11:47 on the 3rd.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ṣaṣṭhī must be present during madhyāhna. It covers 48 of 48 minutes on the 2nd and 48 of 48 on the 3rd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Both middays qualify. Paraviddhā: the second is taken.",
          "fact": "priority: paraviddha → paraviddha · margin 9 s < 300 s"
        },
        {
          "step": "ruling",
          "text": "Campā Ṣaṣṭhī, Harbin, 1981: Thursday 3 December.",
          "fact": "confidence: boundary (margin)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "champa-shashthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 6 Campa sasthi (Maharashtra) (paraviddha). (Special when combined with naksatra Satabhisaj, yoga Vyatipata and Sunday), Skanda sasthi (purvaviddha), Guha sasthi"
          }
        ],
        "not_evaluated": "The row calls the day special with Śatabhiṣaj nakṣatra, Vyatīpāta yoga and a Sunday; none is tested.",
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-03",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-03",
          "confidence": "boundary"
        }
      ],
      "quote": "In Harbin, Campā Ṣaṣṭhī 1981 falls on Thursday 3 December. Ṣaṣṭhī runs from 10:30 on Wed 2 Dec to 11:47 on Thu 3 Dec and covers all of madhyāhna that midday. It also reaches the previous midday for 48 minutes; by the rule the second midday is taken. It is 0 min 09 s from a threshold: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/champa-shashthi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/mitra-saptami",
      "festival": "mitra-saptami",
      "name": "Mitra Saptamī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-04",
      "confidence": "boundary",
      "boundary_reasons": [
        "margin"
      ],
      "boundary_margin_s": 9,
      "anga": {
        "type": "tithi",
        "index": 6,
        "key": "saptami",
        "name": "Saptamī",
        "start": {
          "local": "1981-12-03T11:47:07+08:00",
          "utc": "1981-12-03T03:47:07Z",
          "ms": 376199227304.56415
        },
        "end": {
          "local": "1981-12-04T12:22:08+08:00",
          "utc": "1981-12-04T04:22:08Z",
          "ms": 376287728077.0888
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-03T11:47:07+08:00",
          "utc": "1981-12-03T03:47:07Z",
          "ms": 376199227304.56415
        },
        "end": {
          "local": "1981-12-04T12:22:08+08:00",
          "utc": "1981-12-04T04:22:08Z",
          "ms": 376287728077.0888
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-12-03",
          "window": {
            "start": {
              "local": "1981-12-03T10:58:58+08:00",
              "utc": "1981-12-03T02:58:58Z",
              "ms": 376196337964.99585
            },
            "end": {
              "local": "1981-12-03T11:46:58+08:00",
              "utc": "1981-12-03T03:46:58Z",
              "ms": 376199217964.99585
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        },
        {
          "local_date": "1981-12-04",
          "window": {
            "start": {
              "local": "1981-12-04T10:59:22+08:00",
              "utc": "1981-12-04T02:59:22Z",
              "ms": 376282762223.20166
            },
            "end": {
              "local": "1981-12-04T11:47:22+08:00",
              "utc": "1981-12-04T03:47:22Z",
              "ms": 376285642223.20166
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Saptamī runs from 11:47 on Thu 3 Dec to 12:22 on Fri 4 Dec.",
          "fact": "1981-12-03T03:47:07Z → 1981-12-04T04:22:08Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 10:59–11:47 on the 3rd, 10:59–11:47 on the 4th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Saptamī must be present during madhyāhna. It covers 0 of 48 minutes on the 3rd and 48 of 48 on the 4th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: purvaviddha → only-day · margin 9 s < 300 s"
        },
        {
          "step": "ruling",
          "text": "Mitra Saptamī, Harbin, 1981: Friday 4 December.",
          "fact": "confidence: boundary (margin)"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "mitra-saptami",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 7 Mitra saptami (purvaviddha)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "purvaviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-04",
          "confidence": "boundary"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-03",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Mitra Saptamī 1981 falls on Friday 4 December. Saptamī runs from 11:47 on Thu 3 Dec to 12:22 on Fri 4 Dec and covers all of madhyāhna that midday. It is 0 min 09 s from a threshold: treat the date as contested.",
      "cite": "https://ahargana.org/harbin/festivals/1981/mitra-saptami",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-12-07",
      "festival": "ekadashi",
      "name": "Mokṣadā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-07",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 613,
      "anga": {
        "type": "tithi",
        "index": 10,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-12-07T09:21:18+08:00",
          "utc": "1981-12-07T01:21:18Z",
          "ms": 376536077658.26056
        },
        "end": {
          "local": "1981-12-08T06:51:09+08:00",
          "utc": "1981-12-07T22:51:09Z",
          "ms": 376613469314.172
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-07T09:21:18+08:00",
          "utc": "1981-12-07T01:21:18Z",
          "ms": 376536077658.26056
        },
        "end": {
          "local": "1981-12-08T06:51:09+08:00",
          "utc": "1981-12-07T22:51:09Z",
          "ms": 376613469314.172
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-12-07",
          "window": {
            "start": {
              "local": "1981-12-07T07:00:22+08:00",
              "utc": "1981-12-06T23:00:22Z",
              "ms": 376527621546.81506
            },
            "end": {
              "local": "1981-12-07T07:00:22+08:00",
              "utc": "1981-12-06T23:00:22Z",
              "ms": 376527621546.81506
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-12-08",
          "window": {
            "start": {
              "local": "1981-12-08T07:01:22+08:00",
              "utc": "1981-12-07T23:01:22Z",
              "ms": 376614082412.27997
            },
            "end": {
              "local": "1981-12-08T07:01:22+08:00",
              "utc": "1981-12-07T23:01:22Z",
              "ms": 376614082412.27997
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        }
      ],
      "decided_by": "tithi-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 09:21 on Mon 7 Dec to 06:51 on Tue 8 Dec.",
          "fact": "1981-12-07T01:21:18Z → 1981-12-07T22:51:09Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 07:00 on the 7th and 07:01 on the 8th.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is not on the 7th and is not on the 8th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Neither sunrise qualifies. The day the tithi falls on is taken.",
          "fact": "priority: paraviddha → tithi-day · margin 613 s"
        },
        {
          "step": "ruling",
          "text": "Mokṣadā Ekādaśī, Harbin, 1981: Monday 7 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-07",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-07",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Mokṣadā Ekādaśī 1981 falls on Monday 7 December. Ekādaśī runs from 09:21 on Mon 7 Dec to 06:51 on Tue 8 Dec, and is current at sunrise on neither day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-12-07",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/akhanda-dvadashi",
      "festival": "akhanda-dvadashi",
      "name": "Akhaṇḍa Dvādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-08",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 14995,
      "anga": {
        "type": "tithi",
        "index": 11,
        "key": "dvadashi",
        "name": "Dvādaśī",
        "start": {
          "local": "1981-12-08T06:51:09+08:00",
          "utc": "1981-12-07T22:51:09Z",
          "ms": 376613469314.172
        },
        "end": {
          "local": "1981-12-09T03:46:21+08:00",
          "utc": "1981-12-08T19:46:21Z",
          "ms": 376688781145.28674
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-08T06:51:09+08:00",
          "utc": "1981-12-07T22:51:09Z",
          "ms": 376613469314.172
        },
        "end": {
          "local": "1981-12-09T03:46:21+08:00",
          "utc": "1981-12-08T19:46:21Z",
          "ms": 376688781145.28674
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-12-08",
          "window": {
            "start": {
              "local": "1981-12-08T11:01:05+08:00",
              "utc": "1981-12-08T03:01:05Z",
              "ms": 376628464653.10364
            },
            "end": {
              "local": "1981-12-08T11:49:05+08:00",
              "utc": "1981-12-08T03:49:05Z",
              "ms": 376631344653.10364
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-12-09",
          "window": {
            "start": {
              "local": "1981-12-09T11:01:31+08:00",
              "utc": "1981-12-09T03:01:31Z",
              "ms": 376714891482.6919
            },
            "end": {
              "local": "1981-12-09T11:49:31+08:00",
              "utc": "1981-12-09T03:49:31Z",
              "ms": 376717771482.6919
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Dvādaśī runs from 06:51 on Tue 8 Dec to 03:46 on Wed 9 Dec.",
          "fact": "1981-12-07T22:51:09Z → 1981-12-08T19:46:21Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:01–11:49 on the 8th, 11:02–11:50 on the 9th.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Dvādaśī must be present during madhyāhna. It covers 48 of 48 minutes on the 8th and 0 of 48 on the 9th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: paraviddha → only-day · margin 14995 s"
        },
        {
          "step": "ruling",
          "text": "Akhaṇḍa Dvādaśī, Harbin, 1981: Tuesday 8 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "akhanda-dvadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 12 Matsya dvadasi, Akhanda dvadasi (paraviddha), Vyanjana dvadasi & Dana dvadasi (Orissa)."
          }
        ],
        "kaala": "madhyahna",
        "priority": "paraviddha",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-08",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-08",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Akhaṇḍa Dvādaśī 1981 falls on Tuesday 8 December. Dvādaśī runs from 06:51 on Tue 8 Dec to 03:46 on Wed 9 Dec and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/akhanda-dvadashi",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-12-09",
      "festival": "pradosha-vrata",
      "name": "Śukla Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-09",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 23130,
      "anga": {
        "type": "tithi",
        "index": 12,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-12-09T03:46:21+08:00",
          "utc": "1981-12-08T19:46:21Z",
          "ms": 376688781145.28674
        },
        "end": {
          "local": "1981-12-10T00:16:09+08:00",
          "utc": "1981-12-09T16:16:09Z",
          "ms": 376762568628.0858
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-09T03:46:21+08:00",
          "utc": "1981-12-08T19:46:21Z",
          "ms": 376688781145.28674
        },
        "end": {
          "local": "1981-12-10T00:16:09+08:00",
          "utc": "1981-12-09T16:16:09Z",
          "ms": 376762568628.0858
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-12-08",
          "window": {
            "start": {
              "local": "1981-12-08T15:48:47+08:00",
              "utc": "1981-12-08T07:48:47Z",
              "ms": 376645726893.9273
            },
            "end": {
              "local": "1981-12-08T17:50:36+08:00",
              "utc": "1981-12-08T09:50:36Z",
              "ms": 376653035506.80084
            }
          },
          "covered_min": 0,
          "window_min": 122,
          "qualifies": false
        },
        {
          "local_date": "1981-12-09",
          "window": {
            "start": {
              "local": "1981-12-09T15:48:41+08:00",
              "utc": "1981-12-09T07:48:41Z",
              "ms": 376732121474.9051
            },
            "end": {
              "local": "1981-12-09T17:50:38+08:00",
              "utc": "1981-12-09T09:50:38Z",
              "ms": 376739438441.4852
            }
          },
          "covered_min": 122,
          "window_min": 122,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 03:46 on Wed 9 Dec to 00:16 on Thu 10 Dec.",
          "fact": "1981-12-08T19:46:21Z → 1981-12-09T16:16:09Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 15:49–17:51 on the 8th, 15:49–17:51 on the 9th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 0 of 122 minutes on the 8th and 122 of 122 on the 9th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 23130 s"
        },
        {
          "step": "ruling",
          "text": "Śukla Pradoṣa Vrata, Harbin, 1981: Wednesday 9 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-09",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-09",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śukla Pradoṣa Vrata 1981 falls on Wednesday 9 December. Trayodaśī runs from 03:46 on Wed 9 Dec to 00:16 on Thu 10 Dec and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-12-09",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/dattatreyotpatti",
      "festival": "dattatreyotpatti",
      "name": "Dattātreyotpatti",
      "everyday": "Datta Jayanti",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-11",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 3163,
      "anga": {
        "type": "tithi",
        "index": 14,
        "key": "purnima",
        "name": "Pūrṇimā",
        "start": {
          "local": "1981-12-10T20:30:52+08:00",
          "utc": "1981-12-10T12:30:52Z",
          "ms": 376835451752.3243
        },
        "end": {
          "local": "1981-12-11T16:41:21+08:00",
          "utc": "1981-12-11T08:41:21Z",
          "ms": 376908081367.31335
        },
        "month": {
          "amanta": 8,
          "purnimanta": 8,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Mārgaśīrṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-10T20:30:52+08:00",
          "utc": "1981-12-10T12:30:52Z",
          "ms": 376835451752.3243
        },
        "end": {
          "local": "1981-12-11T16:41:21+08:00",
          "utc": "1981-12-11T08:41:21Z",
          "ms": 376908081367.31335
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-12-10",
          "window": {
            "start": {
              "local": "1981-12-10T15:48:39+08:00",
              "utc": "1981-12-10T07:48:39Z",
              "ms": 376818518778.72
            },
            "end": {
              "local": "1981-12-10T17:50:43+08:00",
              "utc": "1981-12-10T09:50:43Z",
              "ms": 376825843482.77484
            }
          },
          "covered_min": 0,
          "window_min": 122,
          "qualifies": false
        },
        {
          "local_date": "1981-12-11",
          "window": {
            "start": {
              "local": "1981-12-11T15:48:39+08:00",
              "utc": "1981-12-11T07:48:39Z",
              "ms": 376904918811.4615
            },
            "end": {
              "local": "1981-12-11T17:50:51+08:00",
              "utc": "1981-12-11T09:50:51Z",
              "ms": 376912250628.9362
            }
          },
          "covered_min": 53,
          "window_min": 122,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Pūrṇimā runs from 20:31 on Thu 10 Dec to 16:41 on Fri 11 Dec.",
          "fact": "1981-12-10T12:30:52Z → 1981-12-11T08:41:21Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 15:49–17:51 on the 10th, 15:49–17:51 on the 11th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Pūrṇimā must be present during pradoṣa. It covers 0 of 122 minutes on the 10th and 53 of 122 on the 11th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 3163 s"
        },
        {
          "step": "ruling",
          "text": "Dattātreyotpatti, Harbin, 1981: Friday 11 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "dattatreyotpatti",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 104",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "S 15 Dattatreyotpatti (pradosa)."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-11",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-11",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Dattātreyotpatti (Datta Jayanti) 1981 falls on Friday 11 December. Pūrṇimā runs from 20:31 on Thu 10 Dec to 16:41 on Fri 11 Dec and covers 53 of 122 minutes of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/dattatreyotpatti",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/sankashta-chaturthi?on=1981-12-14",
      "festival": "sankashta-chaturthi",
      "name": "Saṅkaṣṭa Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-14",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 32580,
      "anga": {
        "type": "tithi",
        "index": 18,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-12-14T06:34:30+08:00",
          "utc": "1981-12-13T22:34:30Z",
          "ms": 377130869568.7105
        },
        "end": {
          "local": "1981-12-15T04:11:41+08:00",
          "utc": "1981-12-14T20:11:41Z",
          "ms": 377208701159.98047
        },
        "month": {
          "amanta": 8,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-14T06:34:30+08:00",
          "utc": "1981-12-13T22:34:30Z",
          "ms": 377130869568.7105
        },
        "end": {
          "local": "1981-12-15T04:11:41+08:00",
          "utc": "1981-12-14T20:11:41Z",
          "ms": 377208701159.98047
        }
      },
      "kaala": "moonrise",
      "days": [
        {
          "local_date": "1981-12-13",
          "window": {
            "start": {
              "local": "1981-12-13T17:59:23+08:00",
              "utc": "1981-12-13T09:59:23Z",
              "ms": 377085563146.57776
            },
            "end": {
              "local": "1981-12-13T17:59:23+08:00",
              "utc": "1981-12-13T09:59:23Z",
              "ms": 377085563146.57776
            }
          },
          "covered_min": 0,
          "window_min": 0,
          "qualifies": false
        },
        {
          "local_date": "1981-12-14",
          "window": {
            "start": {
              "local": "1981-12-14T19:08:41+08:00",
              "utc": "1981-12-14T11:08:41Z",
              "ms": 377176120734.62585
            },
            "end": {
              "local": "1981-12-14T19:08:41+08:00",
              "utc": "1981-12-14T11:08:41Z",
              "ms": 377176120734.62585
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 06:34 on Mon 14 Dec to 04:12 on Tue 15 Dec.",
          "fact": "1981-12-13T22:34:30Z → 1981-12-14T20:11:41Z"
        },
        {
          "step": "kaala",
          "text": "Moonrise is at 17:59 on the 13th and 19:09 on the 14th.",
          "fact": "moonrise: disc centre, 31′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be current at moonrise. It is not on the 13th and is on the 14th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one moonrise qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 32580 s"
        },
        {
          "step": "ruling",
          "text": "Saṅkaṣṭa Caturthī, Harbin, 1981: Monday 14 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "sankashta-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "not_evaluated": "It is called Aṅgāraka Caturthī when it falls on a Tuesday; the weekday is not tested.",
        "kaala": "moonrise",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-14",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-14",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saṅkaṣṭa Caturthī 1981 falls on Monday 14 December. Caturthī runs from 06:34 on Mon 14 Dec to 04:12 on Tue 15 Dec and is current at moonrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/sankashta-chaturthi?on=1981-12-14",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/ekadashi?on=1981-12-22",
      "festival": "ekadashi",
      "name": "Saphalā Ekādaśī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-22",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 2225,
      "anga": {
        "type": "tithi",
        "index": 25,
        "key": "ekadashi",
        "name": "Ekādaśī",
        "start": {
          "local": "1981-12-21T05:30:01+08:00",
          "utc": "1981-12-20T21:30:01Z",
          "ms": 377731800511.7494
        },
        "end": {
          "local": "1981-12-22T07:49:08+08:00",
          "utc": "1981-12-21T23:49:08Z",
          "ms": 377826548194.08484
        },
        "month": {
          "amanta": 8,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-21T05:30:01+08:00",
          "utc": "1981-12-20T21:30:01Z",
          "ms": 377731800511.7494
        },
        "end": {
          "local": "1981-12-22T07:49:08+08:00",
          "utc": "1981-12-21T23:49:08Z",
          "ms": 377826548194.08484
        }
      },
      "kaala": "sunrise",
      "days": [
        {
          "local_date": "1981-12-21",
          "window": {
            "start": {
              "local": "1981-12-21T07:11:32+08:00",
              "utc": "1981-12-20T23:11:32Z",
              "ms": 377737891720.89386
            },
            "end": {
              "local": "1981-12-21T07:11:32+08:00",
              "utc": "1981-12-20T23:11:32Z",
              "ms": 377737891720.89386
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        },
        {
          "local_date": "1981-12-22",
          "window": {
            "start": {
              "local": "1981-12-22T07:12:03+08:00",
              "utc": "1981-12-21T23:12:03Z",
              "ms": 377824322853.59045
            },
            "end": {
              "local": "1981-12-22T07:12:03+08:00",
              "utc": "1981-12-21T23:12:03Z",
              "ms": 377824322853.59045
            }
          },
          "covered_min": 1,
          "window_min": 0,
          "qualifies": true
        }
      ],
      "decided_by": "paraviddha",
      "explanation": [
        {
          "step": "anga",
          "text": "Ekādaśī runs from 05:30 on Mon 21 Dec to 07:49 on Tue 22 Dec.",
          "fact": "1981-12-20T21:30:01Z → 1981-12-21T23:49:08Z"
        },
        {
          "step": "kaala",
          "text": "Sunrise is at 07:12 on the 21st and 07:12 on the 22nd.",
          "fact": "sunrise: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Ekādaśī must be current at sunrise. It is on the 21st and is on the 22nd.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105"
        },
        {
          "step": "tie_break",
          "text": "Both sunrises qualify. Paraviddhā: the second is taken.",
          "fact": "priority: paraviddha → paraviddha · margin 2225 s"
        },
        {
          "step": "ruling",
          "text": "Saphalā Ekādaśī, Harbin, 1981: Tuesday 22 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "ekadashi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 105",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The general rule prevalent in most part of India is that it is to be observed on the day when the tithi is current at sunrise. If it occurs on two successive days, it is to be observed on the second day. When does not occur on any day, it is to be observed on the day of the tithi, but widows and sannyasins would observe on the next-day."
          }
        ],
        "not_evaluated": "The next-day observance for widows and sannyāsins, the Bengal avoidance of an ekādaśī joined to daśamī, and the Vaiṣṇava aruṇodaya rule belong to other traditions and are not applied.",
        "kaala": "sunrise",
        "priority": "paraviddha",
        "when_absent": "tithi-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-22",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-22",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Saphalā Ekādaśī 1981 falls on Tuesday 22 December. Ekādaśī runs from 05:30 on Mon 21 Dec to 07:49 on Tue 22 Dec and is current at sunrise that day.",
      "cite": "https://ahargana.org/harbin/festivals/1981/ekadashi?on=1981-12-22",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/pradosha-vrata?on=1981-12-23",
      "festival": "pradosha-vrata",
      "name": "Kṛṣṇa Pradoṣa Vrata",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-23",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 10224,
      "anga": {
        "type": "tithi",
        "index": 27,
        "key": "trayodashi",
        "name": "Trayodaśī",
        "start": {
          "local": "1981-12-23T10:22:51+08:00",
          "utc": "1981-12-23T02:22:51Z",
          "ms": 377922170579.766
        },
        "end": {
          "local": "1981-12-24T13:02:21+08:00",
          "utc": "1981-12-24T05:02:21Z",
          "ms": 378018141305.16614
        },
        "month": {
          "amanta": 8,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-23T10:22:51+08:00",
          "utc": "1981-12-23T02:22:51Z",
          "ms": 377922170579.766
        },
        "end": {
          "local": "1981-12-24T13:02:21+08:00",
          "utc": "1981-12-24T05:02:21Z",
          "ms": 378018141305.16614
        }
      },
      "kaala": "pradosha",
      "days": [
        {
          "local_date": "1981-12-23",
          "window": {
            "start": {
              "local": "1981-12-23T15:52:10+08:00",
              "utc": "1981-12-23T07:52:10Z",
              "ms": 377941930429.66595
            },
            "end": {
              "local": "1981-12-23T17:54:57+08:00",
              "utc": "1981-12-23T09:54:57Z",
              "ms": 377949296728.3342
            }
          },
          "covered_min": 123,
          "window_min": 123,
          "qualifies": true
        },
        {
          "local_date": "1981-12-24",
          "window": {
            "start": {
              "local": "1981-12-24T15:52:45+08:00",
              "utc": "1981-12-24T07:52:45Z",
              "ms": 378028365115.7167
            },
            "end": {
              "local": "1981-12-24T17:55:30+08:00",
              "utc": "1981-12-24T09:55:30Z",
              "ms": 378035729937.97363
            }
          },
          "covered_min": 0,
          "window_min": 123,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Trayodaśī runs from 10:23 on Wed 23 Dec to 13:02 on Thu 24 Dec.",
          "fact": "1981-12-23T02:22:51Z → 1981-12-24T05:02:21Z"
        },
        {
          "step": "kaala",
          "text": "Pradoṣa is 2 muhūrtas after sunset: 15:52–17:55 on the 23rd, 15:53–17:55 on the 24th.",
          "fact": "pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Trayodaśī must be present during pradoṣa. It covers 123 of 123 minutes on the 23rd and 0 of 123 on the 24th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one evening qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 10224 s"
        },
        {
          "step": "ruling",
          "text": "Kṛṣṇa Pradoṣa Vrata, Harbin, 1981: Wednesday 23 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "pradosha-vrata",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "Pradosa-vrata — The sukla and krsna trayodasi tithis of each month when cover the period of 'pradosa', are observed as Pradosa-vratas."
          }
        ],
        "kaala": "pradosha",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-23",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-23",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Kṛṣṇa Pradoṣa Vrata 1981 falls on Wednesday 23 December. Trayodaśī runs from 10:23 on Wed 23 Dec to 13:02 on Thu 24 Dec and covers all of pradoṣa that evening.",
      "cite": "https://ahargana.org/harbin/festivals/1981/pradosha-vrata?on=1981-12-23",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/shivaratri?on=1981-12-24",
      "festival": "shivaratri",
      "name": "Śivarātri",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-24",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 26963,
      "anga": {
        "type": "tithi",
        "index": 28,
        "key": "chaturdashi",
        "name": "Caturdaśī",
        "start": {
          "local": "1981-12-24T13:02:21+08:00",
          "utc": "1981-12-24T05:02:21Z",
          "ms": 378018141305.16614
        },
        "end": {
          "local": "1981-12-25T15:40:09+08:00",
          "utc": "1981-12-25T07:40:09Z",
          "ms": 378114009106.9263
        },
        "month": {
          "amanta": 8,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Mārgaśīrṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-24T13:02:21+08:00",
          "utc": "1981-12-24T05:02:21Z",
          "ms": 378018141305.16614
        },
        "end": {
          "local": "1981-12-25T15:40:09+08:00",
          "utc": "1981-12-25T07:40:09Z",
          "ms": 378114009106.9263
        }
      },
      "kaala": "nishita",
      "days": [
        {
          "local_date": "1981-12-24",
          "window": {
            "start": {
              "local": "1981-12-24T23:09:03+08:00",
              "utc": "1981-12-24T15:09:03Z",
              "ms": 378054543199.18024
            },
            "end": {
              "local": "1981-12-24T23:57:03+08:00",
              "utc": "1981-12-24T15:57:03Z",
              "ms": 378057423199.18024
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-12-25",
          "window": {
            "start": {
              "local": "1981-12-25T23:09:32+08:00",
              "utc": "1981-12-25T15:09:32Z",
              "ms": 378140972299.0288
            },
            "end": {
              "local": "1981-12-25T23:57:32+08:00",
              "utc": "1981-12-25T15:57:32Z",
              "ms": 378143852299.0288
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturdaśī runs from 13:02 on Thu 24 Dec to 15:40 on Fri 25 Dec.",
          "fact": "1981-12-24T05:02:21Z → 1981-12-25T07:40:09Z"
        },
        {
          "step": "kaala",
          "text": "Niśītha is 1 ghaṭikā either side of midnight: 23:09–23:57 on the 24th, 23:10–23:58 on the 25th.",
          "fact": "nishita: midnight-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturdaśī must be present during niśītha. It covers 48 of 48 minutes on the 24th and 0 of 48 on the 25th.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one night qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 26963 s"
        },
        {
          "step": "ruling",
          "text": "Śivarātri, Harbin, 1981: Thursday 24 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "shivaratri",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The krsna caturdasi in each month is called 'Sivaratri'. The chief among them is that of Magha. The tithi must cover nisitha (or pradosa in some opinion)."
          }
        ],
        "not_evaluated": "The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.",
        "kaala": "nishita",
        "priority": "unstated",
        "when_absent": "unstated"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-24",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-24",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Śivarātri 1981 falls on Thursday 24 December. Caturdaśī runs from 13:02 on Thu 24 Dec to 15:40 on Fri 25 Dec and covers all of niśītha that night.",
      "cite": "https://ahargana.org/harbin/festivals/1981/shivaratri?on=1981-12-24",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    },
    {
      "id": "/harbin/festivals/1981/vinayaka-chaturthi?on=1981-12-30",
      "festival": "vinayaka-chaturthi",
      "name": "Vināyaka Caturthī",
      "tradition": "smarta",
      "place": "2037013",
      "year": 1981,
      "local_date": "1981-12-30",
      "confidence": "determinate",
      "boundary_reasons": [],
      "boundary_margin_s": 36102,
      "anga": {
        "type": "tithi",
        "index": 3,
        "key": "chaturthi",
        "name": "Caturthī",
        "start": {
          "local": "1981-12-30T00:01:32+08:00",
          "utc": "1981-12-29T16:01:32Z",
          "ms": 378489691859.1289
        },
        "end": {
          "local": "1981-12-31T01:10:39+08:00",
          "utc": "1981-12-30T17:10:39Z",
          "ms": 378580238986.50134
        },
        "month": {
          "amanta": 9,
          "purnimanta": 9,
          "adhika": false,
          "amanta_name": "Pauṣa",
          "purnimanta_name": "Pauṣa"
        }
      },
      "span": {
        "of": "tithi",
        "start": {
          "local": "1981-12-30T00:01:32+08:00",
          "utc": "1981-12-29T16:01:32Z",
          "ms": 378489691859.1289
        },
        "end": {
          "local": "1981-12-31T01:10:39+08:00",
          "utc": "1981-12-30T17:10:39Z",
          "ms": 378580238986.50134
        }
      },
      "kaala": "madhyahna",
      "days": [
        {
          "local_date": "1981-12-30",
          "window": {
            "start": {
              "local": "1981-12-30T11:11:52+08:00",
              "utc": "1981-12-30T03:11:52Z",
              "ms": 378529911871.81934
            },
            "end": {
              "local": "1981-12-30T11:59:52+08:00",
              "utc": "1981-12-30T03:59:52Z",
              "ms": 378532791871.81934
            }
          },
          "covered_min": 48,
          "window_min": 48,
          "qualifies": true
        },
        {
          "local_date": "1981-12-31",
          "window": {
            "start": {
              "local": "1981-12-31T11:12:21+08:00",
              "utc": "1981-12-31T03:12:21Z",
              "ms": 378616341260.2202
            },
            "end": {
              "local": "1981-12-31T12:00:21+08:00",
              "utc": "1981-12-31T04:00:21Z",
              "ms": 378619221260.2202
            }
          },
          "covered_min": 0,
          "window_min": 48,
          "qualifies": false
        }
      ],
      "decided_by": "only-day",
      "explanation": [
        {
          "step": "anga",
          "text": "Caturthī runs from 00:02 on Wed 30 Dec to 01:11 on Thu 31 Dec.",
          "fact": "1981-12-29T16:01:32Z → 1981-12-30T17:10:39Z"
        },
        {
          "step": "kaala",
          "text": "Madhyāhna is 1 ghaṭikā either side of midday: 11:12–12:00 on the 30th, 11:12–12:00 on the 31st.",
          "fact": "madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′"
        },
        {
          "step": "rule",
          "text": "Caturthī must be present during madhyāhna. It covers 48 of 48 minutes on the 30th and 0 of 48 on the 31st.",
          "fact": "Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 108"
        },
        {
          "step": "tie_break",
          "text": "Only one midday qualifies. No tie-break is needed.",
          "fact": "priority: unstated → only-day · margin 36102 s"
        },
        {
          "step": "ruling",
          "text": "Vināyaka Caturthī, Harbin, 1981: Wednesday 30 December.",
          "fact": "confidence: determinate"
        }
      ],
      "rule": {
        "kind": "lunar",
        "id": "vinayaka-chaturthi",
        "references": [
          {
            "text": "Calendar Reform Committee 1955, General Rules for Religious Festivals",
            "locator": "p. 108",
            "url": "https://archive.org/details/calendar_reform_comittee_report",
            "quote": "The sukla caturthi in each month is called Ganesa caturthi or Vinayaka caturthi. It is observed at madhyahna. The chief among them are caturthis of Bhadrapada and Magha. Similarly the krsna caturthi in each month is called Sankasta caturthi, to be observed on the day when the tithi is current at moonrise. It is called Angaraka caturthi if it falls on Tuesday."
          }
        ],
        "kaala": "madhyahna",
        "priority": "unstated",
        "when_absent": "second-day"
      },
      "alternatives": [
        {
          "kind": "profile",
          "profile": "classical@2026.1",
          "local_date": "1981-12-30",
          "confidence": "determinate"
        },
        {
          "kind": "profile",
          "profile": "compat-drikpanchang@2026.1",
          "local_date": "1981-12-30",
          "confidence": "determinate"
        }
      ],
      "quote": "In Harbin, Vināyaka Caturthī 1981 falls on Wednesday 30 December. Caturthī runs from 00:02 on Wed 30 Dec to 01:11 on Thu 31 Dec and covers all of madhyāhna that midday.",
      "cite": "https://ahargana.org/harbin/festivals/1981/vinayaka-chaturthi?on=1981-12-30",
      "method": "pac-rp@2026.1",
      "engine": {
        "version": "0.1.0",
        "ruleset": "2026.3-draft",
        "kernel": "de440-1900-2100",
        "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
        "tzdata": "2026f"
      }
    }
  ],
  "engine": {
    "version": "0.1.0",
    "ruleset": "2026.3-draft",
    "kernel": "de440-1900-2100",
    "kernel_sha256": "7eef444f9e5bd8786b8b5b72e775ecc376991b953a6246ec7a49d2c37434ea74",
    "tzdata": "2026f"
  }
}
