Panchang in Codcod, Western Visayas, Philippines Thu 29 Mar 2018

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 01:53 on Thu 29 Mar to 23:52 on Thu 29 Mar, so only Thursday’s pradosha (17:57–20:19) 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, 05:46 here. Dwadashi ended at 01:53, before it. Trayodashi ends at 23:52, when the lead reaches 156°. The lead passed 0° at the new moon of 17 Mar, so the Moon is waxing: Shukla paksha.

The night of Wed 28 Mar ran from sunset 17:57 Wed to sunrise 05:46, 11 h 49 m. Cut into 15 muhurtas of 47 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 05:46 to 17:57, 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, 17:57 to 05:45 Fri, 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′. Magha spans 120°00′–133°20′; the Moon entered its pada 4 at 130°. It leaves at 11:08, for Purva Phalguni.

Add the Sun's and the Moon's places among the stars: 344° + 130.2° = 474.2°, one full turn and 114.2°. 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 14:57, 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 12:51, when the lead reaches 150°; Taitila until 23:52.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 05:46 to 05:45 Fri, so the hours after midnight still belong to Guruwara.

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: Meena gives Chaitra. The Sun enters Mesha on 14 Apr, inside the month. The next new moon, 16 Apr, finds it in Mesha and begins Vaishakha.

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 Mar, with the Sun in Meena, began Chaitra. This Shukla paksha reads Chaitra in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 17 Mar 2018, 21:11 Sat. Since then the Sun has moved 11.2° round the stars. Vikram Samvat numbers that year 2075; Shaka Samvat numbers it 1940.