Ruling · Rādhāṣṭamī · 1901

Saturday 21 September

Determinatein Riyadh, under the Rashtriya Panchang method. Clear of every threshold by 206 minutes.

Decide it for

RiyadhDelhiKolkataSingaporeSydneyJersey City

24°41′ N 46°43′ E · Asia/Riyadh · GeoNames 108410

The two middays

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

Midday of Friday 20 September

Aṣṭamī is absent from madhyāhna. Not taken.

madhyāhna begins 11:29  12:17 madhyāhna ends
10:4111:0511:2911:5312:1712:4113:05

0 of 48 minutes covered

Midday of Saturday 21 September

Taken. The only midday Aṣṭamī reaches.

madhyāhna begins 11:28  12:16 madhyāhna ends
10:4011:0411:2811:5212:1612:4013:04

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 15:42 on Fri 20 Sep to 17:27 on Sat 21 Sep.

    1901-09-20T12:36:23Z → 1901-09-21T14:20:34Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:29–12:17 on the 20th, 11:28–12:16 on the 21st.

    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 20th and 48 of 48 on the 21st.

    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 12349 s

  5. 05

    Ruling

    Rādhāṣṭamī, Riyadh, 1901: Saturday 21 September.

    confidence: determinate

Say it like this

In Riyadh, Rādhāṣṭamī 1901 falls on Saturday 21 September. Aṣṭamī runs from 15:42 on Fri 20 Sep to 17:27 on Sat 21 Sep and covers all of madhyāhna that midday.

ahargana.org/riyadh/festivals/1901/radhashtami · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingSat 21 Sep
Ahargaṇa, classicalDisc centre, no refractionSat 21 Sep
compat-drikpanchangComparison profileSat 21 Sep
No institution has a recorded ruling for Riyadh.

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 20thCoveredMadhyāhna 21stCoveredRuled
Los Angeles04:36 → 06:2111:2248 min11:220 min20 Sep
Chicago06:36 → 08:2111:2048 min11:190 min20 Sep
Jersey City07:36 → 09:2111:2548 min11:250 min20 Sep
Port of Spain08:36 → 10:2111:3648 min11:350 min20 Sep
London12:36 → 14:2111:300 min11:2948 min21 Sep
Durban14:06 → 15:5110:560 min10:5548 min21 Sep
Dubai16:17 → 18:0211:290 min11:2948 min21 Sep
Delhi17:57 → 19:4211:420 min11:4148 min21 Sep
Kolkata17:57 → 19:4210:570 min10:5748 min21 Sep
Singapore19:31 → 21:1611:290 min11:2948 min21 Sep
Sydney22:36 → 00:2111:250 min11:2548 min21 Sep
Suva00:31 → 02:1611:310 min11:3148 min21 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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