Ruling · Buddha Pūrṇimā (Vaiśākhī Pūrṇimā) · 1981

Monday 18 May

Determinatein Daqing, under the Rashtriya Panchang method. Clear of every threshold by 189 minutes.

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 Monday 18 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

Midday of Tuesday 19 May

Pūrṇimā is absent from madhyāhna. Not taken.

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

0 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 05:41 on Mon 18 May to 08:04 on Tue 19 May.

    1981-05-17T21:41:09Z → 1981-05-19T00:03:35Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:13–12:01 on the 18th, 11:13–12:01 on the 19th.

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

  3. 03

    Rule

    Pūrṇimā must be present during madhyāhna. It covers 48 of 48 minutes on the 18th and 0 of 48 on the 19th.

    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 11350 s

  5. 05

    Ruling

    Buddha Pūrṇimā, Daqing, 1981: Monday 18 May.

    confidence: determinate

Say it like this

In Daqing, Buddha Pūrṇimā (Vesak) 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.

ahargana.org/daqing/festivals/1981/buddha-purnima · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingMon 18 May
Ahargaṇa, classicalDisc centre, no refractionMon 18 May
compat-drikpanchangComparison profileMon 18 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 17thCoveredMadhyāhna 19thCoveredRuled
Los Angeles14:41 → 17:0412:260 min12:260 min18 May
Chicago16:41 → 19:0412:230 min12:230 min18 May
Jersey City17:41 → 20:0412:290 min12:290 min18 May
Port of Spain17:41 → 20:0411:380 min11:390 min18 May
London22:41 → 01:0412:330 min12:330 min18 May
Durban23:41 → 02:0411:280 min11:280 min18 May
Dubai01:41 → 04:0411:510 min11:510 min18 May
Delhi03:11 → 05:3411:540 min11:540 min18 May
Kolkata03:11 → 05:3411:090 min11:090 min18 May
Singapore05:11 → 07:3412:070 min12:070 min18 May
Sydney07:41 → 10:0411:270 min11:270 min18 May
Suva09:41 → 12:0411:390 min11:3925 min18 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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