Panchang in Codcod, Western Visayas, Philippines Tue 29 Sep 2020

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 23:29 on Mon 28 Sep to 01:03 on Wed 30 Sep, so only Tuesday’s pradosha (17:38–20:02) falls within it. No text giving Pradosh Vrat’s time was found; pradosha is Tithika’s convention.

Pradosh Vrat: every date in Codcod

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 144°–156° is the 13th, Shukla Trayodashi. A day takes the tithi in force at its sunrise, 05:35 here. Dwadashi ended at 23:29 Mon, before it. Trayodashi ends at 01:03 Wed, when the lead reaches 156°. The lead passed 0° at the new moon of 17 Sep, so the Moon is waxing: Shukla paksha.

The night of Mon 28 Sep ran from sunset 17:39 Mon to sunrise 05:35, 11 h 56 m. Cut into 15 muhurtas of 47 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 05:35 to 17:38, splits into 8 choghadiyas of 1 h 30 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 17:38 to 05:35 Wed, splits into 8 choghadiyas of 1 h 29 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′. Shatabhisha spans 306°40′–320°00′; the Moon entered its pada 1 at 306°40′. It leaves at 03:17 Wed, for Purva Bhadrapada.

Add the Sun's and the Moon's places among the stars: 162.1° + 309° = 471.1°, one full turn and 111.1°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 106°40′–120°00′ is the 9th, Shula. It ends at 21:54, then Ganda.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Trayodashi is Kaulava and the second Taitila. Kaulava runs until 12:13, when the lead reaches 150°; Taitila until 01:03 Wed.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 05:35 to 05:35 Wed, so the hours after midnight still belong to Mangalawara.

A month normally holds one sankranti, the Sun's entry into a new rashi. From 17 Sep 19:00 Thu to 17 Oct 03:31 Sat the Sun stayed in Kanya, entering Tula at 17 Oct 09:35 Sat, after the new moon. A month with no sankranti is Adhika Ashwina, before Ashwina itself.

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 17 Sep, with the Sun in Kanya, began Ashwina (Adhik). This Shukla paksha reads Ashwina (Adhik) in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 24 Mar 2020, 17:28 Tue. Since then the Sun has moved 182° round the stars. Vikram Samvat numbers that year 2077; Shaka Samvat numbers it 1942.