Ruling · Mahāśivarātri · 2021

Thursday 11 March

Determinatein Chattogram, under the Rashtriya Panchang method. Clear of every threshold by 485 minutes.

Decide it for

ChattogramDelhiKolkataSingaporeSydneyJersey City

22°20′ N 91°50′ E · Asia/Dhaka · GeoNames 1205733

The two nights

One ghaṭī is 24 minutes. Niśītha is 1 ghaṭikā either side of midnight.

Night of Thursday 11 March

Taken. The only night Caturdaśī reaches.

niśītha begins 23:38  00:26 niśītha ends
22:5023:1423:3800:0200:2600:5001:14

48 of 48 minutes covered

Night of Friday 12 March

Caturdaśī is absent from niśītha. Not taken.

niśītha begins 23:38  00:26 niśītha ends
22:5023:1423:3800:0200:2600:5001:14

0 of 48 minutes covered

Caturdaśī presentNiśītha, the window the rule readsThe instant the tithi begins or ends

How it was decided

  1. 01

    Aṅga

    Caturdaśī runs from 15:10 on Thu 11 Mar to 15:33 on Fri 12 Mar.

    2021-03-11T09:10:18Z → 2021-03-12T09:33:02Z

  2. 02

    Kāla

    Niśītha is 1 ghaṭikā either side of midnight: 23:38–00:26 on the 11th, 23:38–00:26 on the 12th.

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

  3. 03

    Rule

    Caturdaśī must be present during niśītha. It covers 48 of 48 minutes on the 11th and 0 of 48 on the 12th.

    Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105

  4. 04

    Tie-break

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

    priority: disputed → only-day · margin 29106 s

  5. 05

    Ruling

    Mahāśivarātri, Chattogram, 2021: Thursday 11 March.

    confidence: determinate

Say it like this

In Chattogram, Mahāśivarātri 2021 falls on Thursday 11 March. Caturdaśī runs from 15:10 on Thu 11 Mar to 15:33 on Fri 12 Mar and covers all of niśītha that night.

ahargana.org/chattogram/festivals/2021/maha-shivaratri · pac-rp@2026.1

Who says what

AuthorityKindDate
Ahargaṇa, pac-rpThis rulingThu 11 Mar
Ahargaṇa, classicalDisc centre, no refractionThu 11 Mar
compat-drikpanchangComparison profileThu 11 Mar
No institution has a recorded ruling for Chattogram.

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

The rule, as data

/rules/maha-shivaratri · ruleset 2026.3-draft

Month
Māgha, amānta
Pakṣa · aṅga
Kṛṣṇa · Caturdaśī
Kāla
Niśītha
Priority
Disputed
Tie-break
Longer coverage, as a boundary
Reference
CRC 1955, p. 105

“K 14 Mahasivaratri (nisithavyapini) — In some opinion it is to be observed on nisitha and in some opinion on pradosa. If occurs on two successive nisithas then according to Hemadri it is to be observed on the first day and according to Madhava, to be observed on the second day” Calendar Reform Committee 1955, General Rules for Religious Festivals, p. 105. The alternative opinion that reads pradoṣa instead of niśītha is not evaluated.

The same rule, elsewhere

Twelve places, west to east. Local clock times.

PlaceCaturdaśīNiśītha 11thCoveredNiśītha 12thCoveredRuled
Los Angeles01:10 → 01:3323:3848 min23:380 min11 Mar
Chicago03:10 → 03:3323:3648 min23:360 min11 Mar
Jersey City04:10 → 04:3323:4248 min23:410 min11 Mar
Port of Spain05:10 → 05:3323:5248 min23:510 min11 Mar
London09:10 → 09:3323:4648 min23:460 min11 Mar
Durban11:10 → 11:3323:4248 min23:420 min11 Mar
Dubai13:10 → 13:3300:0448 min00:040 min11 Mar
Delhi14:40 → 15:0300:0748 min00:060 min11 Mar
Kolkata14:40 → 15:0323:2248 min23:220 min11 Mar
Singapore17:10 → 17:3300:5048 min00:500 min11 Mar
Sydney20:10 → 20:3300:4148 min00:410 min11 Mar
Suva21:10 → 21:3323:5248 min23:520 min11 Mar
Profile · tradition
pac-rp@2026.1 · smarta
Rule
maha-shivaratri@2026.3-draft
Engine · kernel
0.1.0 · de440 7eef…ea74
Boundary margin
300 s

About Ahargaṇa