Ruling · Dattātreyotpatti (Datta Jayanti) · 1905

Monday 11 December

Determinatein Baoding, under the Rashtriya Panchang method. Clear of every threshold by 571 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 Monday 11 December

Taken. The only evening Pūrṇimā reaches.

16:56 sunsetpradoṣa ends 18:52
16:3216:5617:2017:4418:0818:3218:5619:20

116 of 116 minutes covered

Evening of Tuesday 12 December

Pūrṇimā is absent from pradoṣa. Not taken.

16:56 sunsetpradoṣa ends 18:52
16:3216:5617:2017:4418:0818:3218:5619:20

0 of 116 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 05:42 on Mon 11 Dec to 07:25 on Tue 12 Dec.

    1905-12-10T21:41:48Z → 1905-12-11T23:25:18Z

  2. 02

    Kāla

    Pradoṣa is 2 muhūrtas after sunset: 16:56–18:52 on the 11th, 16:56–18:52 on the 12th.

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

  3. 03

    Rule

    Pūrṇimā must be present during pradoṣa. It covers 116 of 116 minutes on the 11th and 0 of 116 on the 12th.

    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 34250 s

  5. 05

    Ruling

    Dattātreyotpatti, Baoding, 1905: Monday 11 December.

    confidence: determinate

Say it like this

In Baoding, Dattātreyotpatti (Datta Jayanti) 1905 falls on Monday 11 December. Pūrṇimā runs from 05:42 on Mon 11 Dec to 07:25 on Tue 12 Dec and covers all of pradoṣa that evening.

ahargana.org/baoding/festivals/1905/dattatreyotpatti · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingMon 11 Dec
Ahargaṇa, classicalDisc centre, no refractionMon 11 Dec
compat-drikpanchangComparison profileMon 11 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 10thCoveredSunset 11thCoveredRuled
Los Angeles13:42 → 15:2516:44113 min16:440 min10 Dec
Chicago15:42 → 17:2516:19119 min16:1966 min10 Dec
Jersey City16:42 → 18:2516:29104 min16:29117 min11 Dec
Port of Spain17:42 → 19:2517:44100 min17:45100 min11 Dec
London21:42 → 23:2515:510 min15:51129 min11 Dec
Durban23:42 → 01:2518:490 min18:5080 min11 Dec
Dubai01:23 → 03:0617:110 min17:11107 min11 Dec
Delhi03:03 → 04:4617:150 min17:16109 min11 Dec
Kolkata03:03 → 04:4616:440 min16:44106 min11 Dec
Singapore04:42 → 06:2517:590 min17:5996 min11 Dec
Sydney07:42 → 09:2518:580 min18:5977 min11 Dec
Suva09:37 → 11:2018:290 min18:3087 min11 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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