Ruling · Rādhāṣṭamī · 2091

Thursday 20 September

Determinatein Daqing, under the Rashtriya Panchang method. Clear of every threshold by 454 minutes.

Decide it for

DaqingDelhiKolkataSingaporeSydneyJersey City

46°35′ N 125°00′ E · Asia/Shanghai · GeoNames 2037860

The two middays

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

Midday of Wednesday 19 September

Aṣṭamī is absent from madhyāhna. Not taken.

madhyāhna begins 11:10  11:58 madhyāhna ends
10:2210:4611:1011:3411:5812:2212:46

0 of 48 minutes covered

Midday of Thursday 20 September

Taken. The only midday Aṣṭamī reaches.

madhyāhna begins 11:09  11:57 madhyāhna ends
10:2110:4511:0911:3311:5712:2112:45

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 21:01 on Wed 19 Sep to 19:31 on Thu 20 Sep.

    2091-09-19T13:00:48Z → 2091-09-20T11:31:19Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:10–11:58 on the 19th, 11:09–11:57 on the 20th.

    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 19th and 48 of 48 on the 20th.

    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 27236 s

  5. 05

    Ruling

    Rādhāṣṭamī, Daqing, 2091: Thursday 20 September.

    confidence: determinate

Say it like this

In Daqing, Rādhāṣṭamī 2091 falls on Thursday 20 September. Aṣṭamī runs from 21:01 on Wed 19 Sep to 19:31 on Thu 20 Sep and covers all of madhyāhna that midday.

ahargana.org/daqing/festivals/2091/radhashtami · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingThu 20 Sep
Ahargaṇa, classicalDisc centre, no refractionThu 20 Sep
compat-drikpanchangComparison profileThu 20 Sep
No institution has a recorded ruling for Daqing.

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 19thCoveredMadhyāhna 20thCoveredRuled
Los Angeles06:01 → 04:3112:2348 min12:220 min19 Sep
Chicago08:01 → 06:3112:2048 min12:200 min19 Sep
Jersey City09:01 → 07:3112:2648 min12:260 min19 Sep
Port of Spain09:01 → 07:3111:3648 min11:360 min19 Sep
London14:01 → 12:3112:300 min12:302 min20 Sep
Durban15:01 → 13:3111:260 min11:2648 min20 Sep
Dubai17:01 → 15:3111:490 min11:4848 min20 Sep
Delhi18:31 → 17:0111:510 min11:5148 min20 Sep
Kolkata18:31 → 17:0111:070 min11:0648 min20 Sep
Singapore21:01 → 19:3112:350 min12:3448 min20 Sep
Sydney23:01 → 21:3111:260 min11:2548 min20 Sep
Suva01:01 → 23:3111:370 min11:3648 min20 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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