Ruling · Guru Pūrṇimā · 1997

Saturday 19 July

Determinatein Tehran, under the Rashtriya Panchang method. Clear of every threshold by 121 minutes.

Decide it for

TehranDelhiKolkataSingaporeSydneyJersey City

35°42′ N 51°25′ E · Asia/Tehran · GeoNames 112931

The two middays

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

Midday of Saturday 19 July

Taken. The only midday Pūrṇimā reaches.

madhyāhna begins 12:46  13:34 madhyāhna ends
11:5812:2212:4613:1013:3413:5814:22

48 of 48 minutes covered

Midday of Sunday 20 July

Pūrṇimā is absent from madhyāhna. Not taken.

madhyāhna begins 12:46  13:34 madhyāhna ends
11:5812:2212:4613:1013:3413:5814:22

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 10:45 on Sat 19 Jul to 07:50 on Sun 20 Jul.

    1997-07-19T06:15:25Z → 1997-07-20T03:20:17Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 12:46–13:34 on the 19th, 12:46–13:34 on the 20th.

    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 19th and 0 of 48 on the 20th.

    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: paraviddha → only-day · margin 7258 s

  5. 05

    Ruling

    Guru Pūrṇimā, Tehran, 1997: Saturday 19 July.

    confidence: determinate

Say it like this

In Tehran, Guru Pūrṇimā 1997 falls on Saturday 19 July. Pūrṇimā runs from 10:45 on Sat 19 Jul to 07:50 on Sun 20 Jul and covers all of madhyāhna that midday.

ahargana.org/tehran/festivals/1997/guru-purnima · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingSat 19 Jul
Ahargaṇa, classicalDisc centre, no refractionSat 19 Jul
compat-drikpanchangComparison profileSat 19 Jul
No institution has a recorded ruling for Tehran.

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

The rule, as data

/rules/guru-purnima · ruleset 2026.3-draft

Month
Āṣāḍha, amānta
Pakṣa · aṅga
Śukla · Pūrṇimā
Kāla
Madhyāhna
Priority
Paraviddhā
Tie-break
Second day
Reference
CRC 1955, p. 102

“S 15 Guru purnima (paraviddha), Vyasa puja (paraviddha, 3 muhurtas after sunrise), Kokila vrata (sayahna vyapini). Siva sayanotsava (pradosavyapini).” Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 102.

The same rule, elsewhere

Twelve places, west to east. Local clock times.

PlacePūrṇimāMadhyāhna 19thCoveredMadhyāhna 20thCoveredRuled
Los Angeles23:15 → 20:2012:3548 min12:350 min19 Jul
Chicago01:15 → 22:2012:3348 min12:330 min19 Jul
Jersey City02:15 → 23:2012:3848 min12:380 min19 Jul
Port of Spain02:15 → 23:2011:4848 min11:480 min19 Jul
London07:15 → 04:2012:4248 min12:420 min19 Jul
Durban08:15 → 05:2011:3848 min11:380 min19 Jul
Dubai10:15 → 07:2012:0148 min12:010 min19 Jul
Delhi11:45 → 08:5012:0348 min12:030 min19 Jul
Kolkata11:45 → 08:5011:1921 min11:190 min19 Jul
Singapore14:15 → 11:2012:470 min12:470 min20 Jul
Sydney16:15 → 13:2011:380 min11:3848 min20 Jul
Suva18:15 → 15:2011:490 min11:4948 min20 Jul
Profile · tradition
pac-rp@2026.1 · smarta
Rule
guru-purnima@2026.3-draft
Engine · kernel
0.1.0 · de440 7eef…ea74
Boundary margin
300 s

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