Ruling · Nāga Pañcamī · 2021

Friday 13 August

Boundaryin Tehran, under the Rashtriya Panchang method. A threshold is only 1 min 41 s away. Say “contested”.

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 Thursday 12 August

Pañcamī is absent from madhyāhna. Not taken.

madhyāhna begins 12:45  13:33 madhyāhna ends
11:5712:2112:4513:0913:3313:5714:21

0 of 48 minutes covered

Midday of Friday 13 August

Taken. Pañcamī reaches neither midday; the rule takes the second day.

madhyāhna begins 12:45  13:33 madhyāhna ends
Pañcamī ends 12:43:13
11:5712:2112:4513:0913:3313:5714:21

0 of 48 minutes covered

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

How it was decided

  1. 01

    Aṅga

    Pañcamī runs from 14:25 on Thu 12 Aug to 12:43 on Fri 13 Aug.

    2021-08-12T09:55:12Z → 2021-08-13T08:13:13Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 12:45–13:33 on the 12th, 12:45–13:33 on the 13th.

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

  3. 03

    Rule

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

    Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103

  4. 04

    Tie-break

    Neither midday qualifies. The rule takes the second day.

    priority: paraviddha → second-day · margin 101 s < 300 s

  5. 05

    Ruling

    Nāga Pañcamī, Tehran, 2021: Friday 13 August.

    confidence: boundary (margin)

Say it like this

In Tehran, Nāga Pañcamī 2021 falls on Friday 13 August. Pañcamī runs from 14:25 on Thu 12 Aug to 12:43 on Fri 13 Aug, and reaches madhyāhna on neither day. It is 1 min 41 s from a threshold: treat the date as contested.

ahargana.org/tehran/festivals/2021/naga-panchami · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingFri 13 Aug
Ahargaṇa, classicalDisc centre, no refractionFri 13 Aug
compat-drikpanchangComparison profileFri 13 Aug
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/naga-panchami · ruleset 2026.3-draft

Month
Śrāvaṇa, amānta
Pakṣa · aṅga
Śukla · Pañcamī
Kāla
Madhyāhna
Priority
Paraviddhā
Tie-break
Second day
Reference
CRC 1955, p. 103

“S 5 Naga pancami (paraviddha)” Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103.

The same rule, elsewhere

Twelve places, west to east. Local clock times.

PlacePañcamīMadhyāhna 12thCoveredMadhyāhna 13thCoveredRuled
Los Angeles02:55 → 01:1312:3448 min12:330 min12 Aug
Chicago04:55 → 03:1312:3148 min12:310 min12 Aug
Jersey City05:55 → 04:1312:3748 min12:370 min12 Aug
Port of Spain05:55 → 04:1311:4748 min11:470 min12 Aug
London10:55 → 09:1312:4148 min12:410 min12 Aug
Durban11:55 → 10:1311:3730 min11:370 min12 Aug
Dubai13:55 → 12:1312:000 min11:5914 min13 Aug
Delhi15:25 → 13:4312:020 min12:0248 min13 Aug
Kolkata15:25 → 13:4311:170 min11:1748 min13 Aug
Singapore17:55 → 16:1312:460 min12:4548 min13 Aug
Sydney19:55 → 18:1311:360 min11:3648 min13 Aug
Suva21:55 → 20:1311:470 min11:4748 min13 Aug
Profile · tradition
pac-rp@2026.1 · smarta
Rule
naga-panchami@2026.3-draft
Engine · kernel
0.1.0 · de440 7eef…ea74
Boundary margin
300 s

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