Ruling · Guru Pūrṇimā · 1920

Thursday 1 July

Determinatein Tehran, under the Rashtriya Panchang method. Clear of every threshold by 21 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 Wednesday 30 June

Qualifies with 48 of 48 minutes. Not taken.

madhyāhna begins 11:39  12:27 madhyāhna ends
10:5111:1511:3912:0312:2712:5113:15

48 of 48 minutes covered

Midday of Thursday 1 July

Taken. Both middays qualify; the rule takes the second.

madhyāhna begins 11:39  12:27 madhyāhna ends
Pūrṇimā ends 12:06:03
10:5111:1511:3912:0312:2712:5113:15

27 of 48 minutes covered, the first 27

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

How it was decided

  1. 01

    Aṅga

    Pūrṇimā runs from 09:40 on Wed 30 Jun to 12:05 on Thu 1 Jul.

    1920-06-30T06:14:56Z → 1920-07-01T08:40:20Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:39–12:27 on the 30th, 11:39–12:27 on the 1st.

    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 30th and 27 of 48 on the 1st.

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

  4. 04

    Tie-break

    Both middays qualify. Paraviddhā: the second is taken.

    priority: paraviddha → paraviddha · margin 1288 s

  5. 05

    Ruling

    Guru Pūrṇimā, Tehran, 1920: Thursday 1 July.

    confidence: determinate

Say it like this

In Tehran, Guru Pūrṇimā 1920 falls on Thursday 1 July. Pūrṇimā runs from 09:40 on Wed 30 Jun to 12:05 on Thu 1 Jul and covers 27 of 48 minutes of madhyāhna that midday. It also reaches the previous midday for 48 minutes; by the rule the second midday is taken.

ahargana.org/tehran/festivals/1920/guru-purnima · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingThu 1 Jul
Ahargaṇa, classicalDisc centre, no refractionThu 1 Jul
compat-drikpanchangComparison profileThu 1 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 30thCoveredMadhyāhna 1stCoveredRuled
Los Angeles22:15 → 00:4011:3248 min11:330 min30 Jun
Chicago01:15 → 03:4012:3048 min12:300 min30 Jun
Jersey City02:15 → 04:4012:3648 min12:360 min30 Jun
Port of Spain02:15 → 04:4011:4548 min11:460 min30 Jun
London07:15 → 09:4012:4048 min12:400 min30 Jun
Durban08:15 → 10:4011:3548 min11:350 min30 Jun
Dubai10:15 → 12:4011:5848 min11:5842 min1 Jul
Delhi11:45 → 14:1012:0048 min12:0148 min1 Jul
Kolkata11:45 → 14:1011:1619 min11:1648 min1 Jul
Singapore13:15 → 15:4011:440 min11:4448 min1 Jul
Sydney16:15 → 18:4011:350 min11:3548 min1 Jul
Suva18:15 → 20:4011:460 min11:4648 min1 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

About Ahargaṇa