Ruling · Mahāṣṭamī (Durgāṣṭamī) · 2025

Monday 29 September

Determinatein Chicago, under the Rashtriya Panchang method. Clear of every threshold by 279 minutes.

Decide it for

41°51′ N 87°39′ W · America/Chicago · GeoNames 4887398

The two middays

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

Midday of Monday 29 September

Taken. The only midday Aṣṭamī reaches.

madhyāhna begins 12:16  13:04 madhyāhna ends
11:2811:5212:1612:4013:0413:2813:52

48 of 48 minutes covered

Midday of Tuesday 30 September

Aṣṭamī is absent from madhyāhna. Not taken.

madhyāhna begins 12:16  13:04 madhyāhna ends
11:2811:5212:1612:4013:0413:2813:52

0 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 06:02 on Mon 29 Sep to 07:37 on Tue 30 Sep.

    2025-09-29T11:02:14Z → 2025-09-30T12:36:37Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 12:16–13:04 on the 29th, 12:16–13:04 on the 30th.

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

  3. 03

    Rule

    Aṣṭamī must be present during madhyāhna. It covers 48 of 48 minutes on the 29th and 0 of 48 on the 30th.

    Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104

  4. 04

    Tie-break

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

    priority: paraviddha → only-day · margin 16769 s

  5. 05

    Ruling

    Mahāṣṭamī, Chicago, 2025: Monday 29 September.

    confidence: determinate

Say it like this

In Chicago, Mahāṣṭamī (Durga Ashtami) 2025 falls on Monday 29 September. Aṣṭamī runs from 06:02 on Mon 29 Sep to 07:37 on Tue 30 Sep and covers all of madhyāhna that midday.

ahargana.org/chicago/festivals/2025/mahashtami · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingMon 29 Sep
Ahargaṇa, classicalDisc centre, no refractionMon 29 Sep
compat-drikpanchangComparison profileMon 29 Sep
No institution has a recorded ruling for Chicago.

Institutional rulings are recorded with a source address, and are never edited to agree.

The rule, as data

/rules/mahashtami · ruleset 2026.3-draft

Month
Āśvina, amānta
Pakṣa · aṅga
Śukla · Aṣṭamī
Kāla
Madhyāhna
Priority
Paraviddhā
Tie-break
Second day
Reference
CRC 1955, p. 104

“S 8 Mahastami (paraviddha)” Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104.

The same rule, elsewhere

Twelve places, west to east. Local clock times.

PlaceAṣṭamīMadhyāhna 29thCoveredMadhyāhna 30thCoveredRuled
Los Angeles04:02 → 05:3712:1948 min12:190 min29 Sep
Chicago06:02 → 07:3712:1648 min12:160 min29 Sep
Jersey City07:02 → 08:3712:2248 min12:220 min29 Sep
Port of Spain07:02 → 08:3711:3248 min11:320 min29 Sep
London12:02 → 13:3712:2648 min12:2648 min30 Sep
Durban13:02 → 14:3711:220 min11:2248 min30 Sep
Dubai15:02 → 16:3711:450 min11:4548 min30 Sep
Delhi16:32 → 18:0711:470 min11:4748 min30 Sep
Kolkata16:32 → 18:0711:030 min11:0248 min30 Sep
Singapore19:02 → 20:3712:310 min12:3148 min30 Sep
Sydney21:02 → 22:3711:220 min11:2148 min30 Sep
Suva23:02 → 00:3711:330 min11:3348 min30 Sep
Profile · tradition
pac-rp@2026.1 · smarta
Rule
mahashtami@2026.3-draft
Engine · kernel
0.1.0 · de440 7eef…ea74
Boundary margin
300 s