Ruling · Rādhāṣṭamī · 2045

Monday 18 September

Determinatein Tehran, under the Rashtriya Panchang method. Clear of every threshold by 248 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 Sunday 17 September

Aṣṭamī is absent from madhyāhna. Not taken.

madhyāhna begins 11:34  12:22 madhyāhna ends
10:4611:1011:3411:5812:2212:4613:10

0 of 48 minutes covered

Midday of Monday 18 September

Taken. The only midday Aṣṭamī reaches.

madhyāhna begins 11:34  12:22 madhyāhna ends
10:4611:1011:3411:5812:2212:4613:10

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 16:31 on Sun 17 Sep to 17:41 on Mon 18 Sep.

    2045-09-17T13:00:41Z → 2045-09-18T14:10:58Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:34–12:22 on the 17th, 11:34–12:22 on the 18th.

    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 17th and 48 of 48 on the 18th.

    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 14892 s

  5. 05

    Ruling

    Rādhāṣṭamī, Tehran, 2045: Monday 18 September.

    confidence: determinate

Say it like this

In Tehran, Rādhāṣṭamī 2045 falls on Monday 18 September. Aṣṭamī runs from 16:31 on Sun 17 Sep to 17:41 on Mon 18 Sep and covers all of madhyāhna that midday.

ahargana.org/tehran/festivals/2045/radhashtami · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingMon 18 Sep
Ahargaṇa, classicalDisc centre, no refractionMon 18 Sep
compat-drikpanchangComparison profileMon 18 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 17thCoveredMadhyāhna 18thCoveredRuled
Los Angeles06:01 → 07:1112:2348 min12:230 min17 Sep
Chicago08:01 → 09:1112:2148 min12:200 min17 Sep
Jersey City09:01 → 10:1112:2648 min12:260 min17 Sep
Port of Spain09:01 → 10:1111:3648 min11:360 min17 Sep
London14:01 → 15:1112:300 min12:3048 min18 Sep
Durban15:01 → 16:1111:270 min11:2648 min18 Sep
Dubai17:01 → 18:1111:490 min11:4948 min18 Sep
Delhi18:31 → 19:4111:510 min11:5148 min18 Sep
Kolkata18:31 → 19:4111:070 min11:0748 min18 Sep
Singapore21:01 → 22:1112:350 min12:3548 min18 Sep
Sydney23:01 → 00:1111:260 min11:2648 min18 Sep
Suva01:01 → 02:1111:370 min11:3748 min18 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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