Ruling · Durgā Navamī · 2018

Saturday 17 November

Boundaryin Shaoxing, under the Rashtriya Panchang method. A threshold is only 4 min 11 s away. Say “contested”.

Decide it for

ShaoxingDelhiKolkataSingaporeSydneyJersey City

30°00′ N 120°35′ E · Asia/Shanghai · GeoNames 1795855

The two middays

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

Midday of Friday 16 November

Navamī is absent from madhyāhna. Not taken.

madhyāhna begins 11:18  12:06 madhyāhna ends
Navamī begins 12:10:25
10:3010:5411:1811:4212:0612:3012:54

0 of 48 minutes covered

Midday of Saturday 17 November

Taken. The only midday Navamī reaches.

madhyāhna begins 11:18  12:06 madhyāhna ends
10:3010:5411:1811:4212:0612:3012:54

48 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 12:10 on Fri 16 Nov to 14:25 on Sat 17 Nov.

    2018-11-16T04:10:26Z → 2018-11-17T06:24:34Z

  2. 02

    Kāla

    Madhyāhna is 1 ghaṭikā either side of midday: 11:18–12:06 on the 16th, 11:18–12:06 on the 17th.

    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 16th and 48 of 48 on the 17th.

    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: purvaviddha → only-day · margin 251 s < 300 s

  5. 05

    Ruling

    Durgā Navamī, Shaoxing, 2018: Saturday 17 November.

    confidence: boundary (margin)

Say it like this

In Shaoxing, Durgā Navamī 2018 falls on Saturday 17 November. Navamī runs from 12:10 on Fri 16 Nov to 14:25 on Sat 17 Nov and covers all of madhyāhna that midday. It is 4 min 11 s from a threshold: treat the date as contested.

ahargana.org/shaoxing/festivals/2018/durga-navami · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingSat 17 Nov
Ahargaṇa, classicalDisc centre, no refractionSat 17 Nov
compat-drikpanchangComparison profileFri 16 Nov
No institution has a recorded ruling for Shaoxing.

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 16thCoveredMadhyāhna 17thCoveredRuled
Los Angeles20:10 → 22:2511:1448 min11:140 min16 Nov
Chicago22:10 → 00:2511:1148 min11:110 min16 Nov
Jersey City23:10 → 01:2511:1748 min11:170 min16 Nov
Port of Spain00:10 → 02:2511:2748 min11:270 min16 Nov
London04:10 → 06:2511:2148 min11:210 min16 Nov
Durban06:10 → 08:2511:1748 min11:170 min16 Nov
Dubai08:10 → 10:2511:3948 min11:400 min16 Nov
Delhi09:40 → 11:5511:4248 min11:4213 min16 Nov
Kolkata09:40 → 11:5510:5748 min10:5748 min16 Nov
Singapore12:10 → 14:2512:2548 min12:2548 min16 Nov
Sydney15:10 → 17:2512:160 min12:1648 min17 Nov
Suva17:10 → 19:2512:270 min12:2748 min17 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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