Ruling · Buddha Pūrṇimā · 1911

Saturday 13 May

Boundaryin Daqing, under the Rashtriya Panchang method. A threshold is only 3 min 30 s away. Say “contested”.

Decide it for

DaqingDelhiKolkataSingaporeSydneyJersey City

46°35′ N 125°00′ E · Asia/Shanghai · GeoNames 2037860

The two middays

One ghaṭī is 24 minutes. Madhyāhna is 1 ghaṭikā either side of midday.

Midday of Friday 12 May

Pūrṇimā is absent from madhyāhna. Not taken.

madhyāhna begins 11:13  12:01 madhyāhna ends
Pūrṇimā begins 12:04:08
10:2510:4911:1311:3712:0112:2512:49

0 of 48 minutes covered

Midday of Saturday 13 May

Taken. The only midday Pūrṇimā reaches.

madhyāhna begins 11:13  12:01 madhyāhna ends
10:2510:4911:1311:3712:0112:2512:49

48 of 48 minutes covered

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

How it was decided

  1. 01

    Aṅga

    Pūrṇimā runs from 12:04 on Fri 12 May to 14:09 on Sat 13 May.

    1911-05-12T04:04:08Z → 1911-05-13T06:09:27Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:13–12:01 on the 12th, 11:13–12:01 on the 13th.

    madhyahna: midday-pm-1-ghatika · sunrise and sunset: upper limb, 31′ + 16′

  3. 03

    Rule

    Pūrṇimā must be present during madhyāhna. It covers 0 of 48 minutes on the 12th and 48 of 48 on the 13th.

    Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102

  4. 04

    Tie-break

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

    priority: unstated → only-day · margin 210 s < 300 s

  5. 05

    Ruling

    Buddha Pūrṇimā, Daqing, 1911: Saturday 13 May.

    confidence: boundary (margin)

Say it like this

In Daqing, Buddha Pūrṇimā 1911 falls on Saturday 13 May. Pūrṇimā runs from 12:04 on Fri 12 May to 14:09 on Sat 13 May and covers all of madhyāhna that midday. It is 3 min 30 s from a threshold: treat the date as contested.

ahargana.org/daqing/festivals/1911/buddha-purnima · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingSat 13 May
Ahargaṇa, classicalDisc centre, no refractionSat 13 May
compat-drikpanchangComparison profileSat 13 May
No institution has a recorded ruling for Daqing.

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

The rule, as data

/rules/buddha-purnima · ruleset 2026.3-draft

Month
Vaiśākha, amānta
Pakṣa · aṅga
Śukla · Pūrṇimā
Kāla
Madhyāhna
Priority
Unstated
Tie-break
Longer coverage, as a boundary
Reference
CRC 1955, p. 102

“S 15 Sampat gauri vrata (paraviddha), Phuladola (Bengal & Orissa) (paraviddha), Gandhesvari puja (Bengal) (purvaviddha), Buddha purnima, Vaisakhi purnima.” Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102.

The same rule, elsewhere

Twelve places, west to east. Local clock times.

PlacePūrṇimāMadhyāhna 12thCoveredMadhyāhna 13thCoveredRuled
Los Angeles20:04 → 22:0911:2548 min11:250 min12 May
Chicago22:04 → 00:0911:2348 min11:230 min12 May
Jersey City23:04 → 01:0911:2948 min11:290 min12 May
Port of Spain00:04 → 02:0911:3848 min11:380 min12 May
London04:04 → 06:0911:3348 min11:330 min12 May
Durban06:04 → 08:0911:2848 min11:280 min12 May
Dubai07:45 → 09:5011:3248 min11:320 min12 May
Delhi09:34 → 11:3911:5348 min11:530 min12 May
Kolkata09:34 → 11:3911:0948 min11:0931 min12 May
Singapore11:04 → 13:0911:3748 min11:3748 min12 May
Sydney14:04 → 16:0911:270 min11:2748 min13 May
Suva15:59 → 18:0411:330 min11:3348 min13 May
Profile · tradition
pac-rp@2026.1 · smarta
Rule
buddha-purnima@2026.3-draft
Engine · kernel
0.1.0 · de440 7eef…ea74
Boundary margin
300 s

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