Ruling · Dattātreyotpatti (Datta Jayanti) · 1961

Thursday 21 December

Determinatein Baoding, under the Rashtriya Panchang method. Clear of every threshold by 498 minutes.

Decide it for

BaodingDelhiKolkataSingaporeSydneyJersey City

38°52′ N 115°28′ E · Asia/Shanghai · GeoNames 1816971

The two evenings

One ghaṭī is 24 minutes. Pradoṣa is 2 muhūrtas after sunset.

Evening of Thursday 21 December

Taken. The only evening Pūrṇimā reaches.

16:59 sunsetpradoṣa ends 18:56
16:3516:5917:2317:4718:1118:3518:5919:23

117 of 117 minutes covered

Evening of Friday 22 December

Pūrṇimā is absent from pradoṣa. Not taken.

16:59 sunsetpradoṣa ends 18:56
16:3516:5917:2317:4718:1118:3518:5919:23

0 of 117 minutes covered

Pūrṇimā presentPradoṣa, the window the rule readsThe instant the tithi begins or ends

How it was decided

  1. 01

    Aṅga

    Pūrṇimā runs from 08:31 on Thu 21 Dec to 08:42 on Fri 22 Dec.

    1961-12-21T00:31:11Z → 1961-12-22T00:41:48Z

  2. 02

    Kāla

    Pradoṣa is 2 muhūrtas after sunset: 16:59–18:56 on the 21st, 16:59–18:56 on the 22nd.

    pradosha: night-muhurta-1-2 · sunrise and sunset: upper limb, 31′ + 16′

  3. 03

    Rule

    Pūrṇimā must be present during pradoṣa. It covers 117 of 117 minutes on the 21st and 0 of 117 on the 22nd.

    Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104

  4. 04

    Tie-break

    Only one evening qualifies. No tie-break is needed.

    priority: unstated → only-day · margin 29861 s

  5. 05

    Ruling

    Dattātreyotpatti, Baoding, 1961: Thursday 21 December.

    confidence: determinate

Say it like this

In Baoding, Dattātreyotpatti (Datta Jayanti) 1961 falls on Thursday 21 December. Pūrṇimā runs from 08:31 on Thu 21 Dec to 08:42 on Fri 22 Dec and covers all of pradoṣa that evening.

ahargana.org/baoding/festivals/1961/dattatreyotpatti · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingThu 21 Dec
Ahargaṇa, classicalDisc centre, no refractionThu 21 Dec
compat-drikpanchangComparison profileThu 21 Dec
No institution has a recorded ruling for Baoding.

Institutional rulings are recorded with a source address, and are never edited to agree.

The rule, as data

/rules/dattatreyotpatti · ruleset 2026.3-draft

Month
Mārgaśīrṣa, amānta
Pakṣa · aṅga
Śukla · Pūrṇimā
Kāla
Pradoṣa
Priority
Unstated
Tie-break
Longer coverage, as a boundary
Reference
CRC 1955, p. 104

“S 15 Dattatreyotpatti (pradosa).” Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104.

The same rule, elsewhere

Twelve places, west to east. Local clock times.

PlacePūrṇimāSunset 21stCoveredSunset 22ndCoveredRuled
Los Angeles16:31 → 16:4216:470 min16:480 min20 Dec
Chicago18:31 → 18:4216:22119 min16:230 min21 Dec
Jersey City19:31 → 19:4216:32118 min16:320 min21 Dec
Port of Spain20:31 → 20:4217:49100 min17:500 min21 Dec
London00:31 → 00:4215:53130 min15:530 min21 Dec
Durban02:31 → 02:4218:5680 min18:560 min21 Dec
Dubai04:31 → 04:4217:34108 min17:340 min21 Dec
Delhi06:01 → 06:1217:28110 min17:290 min21 Dec
Kolkata06:01 → 06:1216:57106 min16:570 min21 Dec
Singapore08:01 → 08:1218:3496 min18:340 min21 Dec
Sydney10:31 → 10:4219:0577 min19:060 min21 Dec
Suva12:31 → 12:4218:4186 min18:410 min21 Dec
Profile · tradition
pac-rp@2026.1 · smarta
Rule
dattatreyotpatti@2026.3-draft
Engine · kernel
0.1.0 · de440 7eef…ea74
Boundary margin
300 s

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