Ruling · Dattātreyotpatti (Datta Jayanti) · 1920

Saturday 25 December

Determinatein Baoding, under the Rashtriya Panchang method. Clear of every threshold by 100 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 Friday 24 December

Pūrṇimā is absent from pradoṣa. Not taken.

17:01 sunsetpradoṣa ends 18:57
16:3717:0117:2517:4918:1318:3719:0119:25

0 of 117 minutes covered

Evening of Saturday 25 December

Taken. The only evening Pūrṇimā reaches.

17:01 sunsetpradoṣa ends 18:58
16:3717:0117:2517:4918:1318:3719:0119:25

117 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 00:23 on Sat 25 Dec to 20:38 on Sat 25 Dec.

    1920-12-24T16:22:47Z → 1920-12-25T12:38:12Z

  2. 02

    Kāla

    Pradoṣa is 2 muhūrtas after sunset: 17:01–18:57 on the 24th, 17:01–18:58 on the 25th.

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

  3. 03

    Rule

    Pūrṇimā must be present during pradoṣa. It covers 0 of 117 minutes on the 24th and 117 of 117 on the 25th.

    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 6026 s

  5. 05

    Ruling

    Dattātreyotpatti, Baoding, 1920: Saturday 25 December.

    confidence: determinate

Say it like this

In Baoding, Dattātreyotpatti (Datta Jayanti) 1920 falls on Saturday 25 December. Pūrṇimā runs from 00:23 on Sat 25 Dec to 20:38 on Sat 25 Dec and covers all of pradoṣa that evening.

ahargana.org/baoding/festivals/1920/dattatreyotpatti · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingSat 25 Dec
Ahargaṇa, classicalDisc centre, no refractionSat 25 Dec
compat-drikpanchangComparison profileSat 25 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 24thCoveredSunset 25thCoveredRuled
Los Angeles08:23 → 04:3816:49113 min16:500 min24 Dec
Chicago10:23 → 06:3816:24119 min16:250 min24 Dec
Jersey City11:23 → 07:3816:33118 min16:340 min24 Dec
Port of Spain12:23 → 08:3817:51100 min17:510 min24 Dec
London16:23 → 12:3815:55101 min15:550 min24 Dec
Durban18:23 → 14:3818:5780 min18:580 min24 Dec
Dubai20:23 → 16:3817:350 min17:360 min24 Dec
Delhi21:53 → 18:0817:300 min17:3038 min25 Dec
Kolkata21:53 → 18:0816:580 min16:5969 min25 Dec
Singapore23:23 → 19:3818:050 min18:0692 min25 Dec
Sydney02:23 → 22:3819:070 min19:0777 min25 Dec
Suva04:23 → 00:3818:420 min18:4386 min25 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

About Ahargaṇa