Panchang in Codcod, Western Visayas, Philippines Fri 10 Sep 1920

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 03:55 on Fri 10 Sep to 01:19 on Sat 11 Sep, so only Friday’s pradosha (17:51–20:12) falls within it. No text giving Pradosh Vrat’s time was found; pradosha is Tithika’s convention.

Pradosh Vrat: every date in Codcod

Shiva’s worship centres on nishitha, the midnight muhurta. Chaturdashi runs from 01:19 on Sat 11 Sep to 22:54 on Sat 11 Sep, between the two nights’ nishitha, touching neither. The Nirnayasindhu then takes the earlier day: Fri 10 Sep. No text giving Masik Shivratri’s time was found; nishitha is Tithika’s convention.

Masik Shivratri: every date in Codcod

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 324°–336° is the 28th, Krishna Trayodashi. A day takes the tithi in force at its sunrise, 05:37 here. Dwadashi ended at 03:55, before it. Trayodashi ends at 01:19 Sat, when the lead reaches 336°. The lead passed 180° at the full moon of 29 Aug, so the Moon is waning: Krishna paksha.

The night of Thu 9 Sep ran from sunset 17:51 Thu to sunrise 05:37, 11 h 46 m. Cut into 15 muhurtas of 47 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 05:37 to 17:51, splits into 8 choghadiyas of 1 h 31 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 17:51 to 05:37 Sat, splits into 8 choghadiyas of 1 h 28 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The fixed stars divide the Moon's path into 27 nakshatras of 13°20′, each in 4 padas of 3°20′. Ashlesha spans 106°40′–120°00′; the Moon entered its pada 1 at 106°40′. It leaves at 23:47, for Magha.

Add the Sun's and the Moon's places among the stars: 144.1° + 109.1° = 253.2°. The sum, cut into 27 parts of 13°20′, gives the yoga: 240°00′–253°20′ is the 19th, Parigha. It ends at 05:51, then Shiva.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Trayodashi is Garaja and the second Vanija. Garaja runs until 14:36, when the lead reaches 330°; Vanija until 01:19 Sat.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 05:37 to 05:37 Sat, so the hours after midnight still belong to Shukrawara.

An amanta month runs from new moon to new moon and takes its name from the rashi the Sun is in at the new moon that begins it: Karka gives Shravana. The Sun enters Simha on 16 Aug, inside the month. The next new moon, 12 Sep, finds it in Simha and begins Bhadrapada.

A purnimanta month runs from full moon to full moon, so its waning half comes first. It shares its name with the amanta month that its second half falls in: the new moon of 12 Sep, with the Sun in Simha, begins Bhadrapada. Until then this Krishna paksha reads Bhadrapada here, and Shravana in the amanta count.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 20 Mar 1920, 18:55 Sat. Since then the Sun has moved 167.3° round the stars. Vikram Samvat numbers that year 1977; Shaka Samvat numbers it 1842.