Ruling · Rādhāṣṭamī · 1987

Tuesday 1 September

Determinatein Tehran, under the Rashtriya Panchang method. Clear of every threshold by 360 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 Monday 31 August

Aṣṭamī is absent from madhyāhna. Not taken.

madhyāhna begins 11:41  12:29 madhyāhna ends
10:5311:1711:4112:0512:2912:5313:17

0 of 48 minutes covered

Midday of Tuesday 1 September

Taken. The only midday Aṣṭamī reaches.

madhyāhna begins 11:40  12:28 madhyāhna ends
10:5211:1611:4012:0412:2812:5213:16

48 of 48 minutes covered

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

How it was decided

  1. 01

    Aṅga

    Aṣṭamī runs from 19:58 on Mon 31 Aug to 18:28 on Tue 1 Sep.

    1987-08-31T16:28:14Z → 1987-09-01T14:58:18Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:41–12:29 on the 31st, 11:40–12:28 on the 1st.

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

  3. 03

    Rule

    Aṣṭamī must be present during madhyāhna. It covers 0 of 48 minutes on the 31st and 48 of 48 on the 1st.

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

  4. 04

    Tie-break

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

    priority: unstated → only-day · margin 21605 s

  5. 05

    Ruling

    Rādhāṣṭamī, Tehran, 1987: Tuesday 1 September.

    confidence: determinate

Say it like this

In Tehran, Rādhāṣṭamī 1987 falls on Tuesday 1 September. Aṣṭamī runs from 19:58 on Mon 31 Aug to 18:28 on Tue 1 Sep and covers all of madhyāhna that midday.

ahargana.org/tehran/festivals/1987/radhashtami · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingTue 1 Sep
Ahargaṇa, classicalDisc centre, no refractionTue 1 Sep
compat-drikpanchangComparison profileTue 1 Sep
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/radhashtami · ruleset 2026.3-draft

Month
Bhādrapada, amānta
Pakṣa · aṅga
Śukla · Aṣṭamī
Kāla
Madhyāhna
Priority
Unstated
Tie-break
Longer coverage, as a boundary
Reference
CRC 1955, p. 103

“S 8 Durvastami (purvaviddha — S 8 of saura Bhadra except Bengal), Mahalaksmi vratarambha, Radhastami (madhyahna vyapini)” Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 103.

The same rule, elsewhere

Twelve places, west to east. Local clock times.

PlaceAṣṭamīMadhyāhna 31stCoveredMadhyāhna 1stCoveredRuled
Los Angeles09:28 → 07:5812:2948 min12:290 min31 Aug
Chicago11:28 → 09:5812:2748 min12:260 min31 Aug
Jersey City12:28 → 10:5812:3248 min12:320 min31 Aug
Port of Spain12:28 → 10:5811:422 min11:420 min31 Aug
London17:28 → 15:5812:360 min12:3648 min1 Sep
Durban18:28 → 16:5811:330 min11:3248 min1 Sep
Dubai20:28 → 18:5811:550 min11:5548 min1 Sep
Delhi21:58 → 20:2811:570 min11:5748 min1 Sep
Kolkata21:58 → 20:2811:130 min11:1348 min1 Sep
Singapore00:28 → 22:5812:410 min12:4148 min1 Sep
Sydney02:28 → 00:5811:320 min11:3248 min1 Sep
Suva04:28 → 02:5811:430 min11:4348 min1 Sep
Profile · tradition
pac-rp@2026.1 · smarta
Rule
radhashtami@2026.3-draft
Engine · kernel
0.1.0 · de440 7eef…ea74
Boundary margin
300 s

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