Ruling · Durgā Navamī · 1900

Thursday 1 November

Boundaryin Phoenix, under the Rashtriya Panchang method. A threshold is only 1 min 27 s away. Say “contested”.

Decide it for

PhoenixDelhiKolkataSingaporeSydneyJersey City

33°27′ N 112°04′ W · America/Phoenix · GeoNames 5308655

The two middays

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

Midday of Wednesday 31 October

Navamī is absent from madhyāhna. Not taken.

madhyāhna begins 11:48  12:36 madhyāhna ends
Navamī begins 12:37:14
11:0011:2411:4812:1212:3613:0013:24

0 of 48 minutes covered

Midday of Thursday 1 November

Taken. Navamī reaches neither midday; the rule takes the second day.

madhyāhna begins 11:48  12:36 madhyāhna ends
11:0011:2411:4812:1212:3613:0013:24

0 of 48 minutes covered

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

How it was decided

  1. 01

    Aṅga

    Navamī runs from 12:37 on Wed 31 Oct to 10:48 on Thu 1 Nov.

    1900-10-31T19:37:15Z → 1900-11-01T17:48:24Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:48–12:36 on the 31st, 11:48–12:36 on the 1st.

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

  3. 03

    Rule

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

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

  4. 04

    Tie-break

    Neither midday qualifies. The rule takes the second day.

    priority: purvaviddha → second-day · margin 87 s < 300 s

  5. 05

    Ruling

    Durgā Navamī, Phoenix, 1900: Thursday 1 November.

    confidence: boundary (margin)

Say it like this

In Phoenix, Durgā Navamī 1900 falls on Thursday 1 November. Navamī runs from 12:37 on Wed 31 Oct to 10:48 on Thu 1 Nov, and reaches madhyāhna on neither day. It is 1 min 27 s from a threshold: treat the date as contested.

ahargana.org/phoenix/festivals/1900/durga-navami · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingThu 1 Nov
Ahargaṇa, classicalDisc centre, no refractionThu 1 Nov
compat-drikpanchangComparison profileWed 31 Oct
No institution has a recorded ruling for Phoenix.

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

The rule, as data

/rules/durga-navami · ruleset 2026.3-draft

Month
Kārtika, amānta
Pakṣa · aṅga
Śukla · Navamī
Kāla
Madhyāhna
Priority
Pūrvaviddhā
Tie-break
First day
Reference
CRC 1955, p. 104

“S 9 Aksaya navami (purvahnavyapini), Jagaddhatri puja (Bengal), (udayavyapini one muhurta), Anla navami (Orissa), Durga navami (purvaviddha), Gauri vrata.” Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 104.

The same rule, elsewhere

Twelve places, west to east. Local clock times.

PlaceNavamīMadhyāhna 31stCoveredMadhyāhna 1stCoveredRuled
Los Angeles11:37 → 09:4811:1223 min11:120 min31 Oct
Chicago13:37 → 11:4811:100 min11:1038 min1 Nov
Jersey City14:37 → 12:4811:160 min11:1648 min1 Nov
Port of Spain15:37 → 13:4811:260 min11:2648 min1 Nov
London19:37 → 17:4811:200 min11:2048 min1 Nov
Durban21:07 → 19:1810:460 min10:4648 min1 Nov
Dubai23:18 → 21:2911:190 min11:1948 min1 Nov
Delhi00:58 → 23:0911:320 min11:3248 min1 Nov
Kolkata00:58 → 23:0910:470 min10:4748 min1 Nov
Singapore02:32 → 00:4311:190 min11:1948 min1 Nov
Sydney05:37 → 03:4811:150 min11:1548 min1 Nov
Suva07:32 → 05:4311:210 min11:2148 min1 Nov
Profile · tradition
pac-rp@2026.1 · smarta
Rule
durga-navami@2026.3-draft
Engine · kernel
0.1.0 · de440 7eef…ea74
Boundary margin
300 s

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