Panchang in Codcod, Western Visayas, Philippines Tue 20 Jan 1981

Purnima follows the tithi at sunrise. Purnima runs from 16:49 on Mon 19 Jan to 15:38 on Tue 20 Jan, so it holds sunrise only on Tue 20 Jan, at 06:10. No text giving Purnima’s time was found; sunrise is Tithika’s convention.

Purnima: every date in Codcod

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 168°–180° is the 15th, Shukla Purnima. A day takes the tithi in force at its sunrise, 06:10 here. Chaturdashi ended at 16:49 Mon, before it. Purnima ends at 15:38, when the lead reaches 180°. The lead passed 0° at the new moon of 6 Jan, so the Moon is waxing: Shukla paksha.

The night of Mon 19 Jan ran from sunset 17:45 Mon to sunrise 06:10, 12 h 25 m. Cut into 15 muhurtas of 49 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:10 to 17:46, splits into 8 choghadiyas of 1 h 27 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 17:46 to 06:10 Wed, splits into 8 choghadiyas of 1 h 33 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′. Punarvasu spans 80°00′–93°20′; the Moon entered its pada 4 at 90°. It leaves at 09:53, for Pushya.

Add the Sun's and the Moon's places among the stars: 276.2° + 91.2° = 367.4°, one full turn and 7.4°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 0°00′–13°20′ is the 1st, Vishkambha. It ends at 15:55, then Priti.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Purnima is Vishti and the second Bava. Vishti ended at 04:10, when the lead reached 174°; Bava runs until 15:38.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:10 to 06:10 Wed, so the hours after midnight still belong to Mangalawara.

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: Dhanu gives Pausha. The Sun enters Makara on 14 Jan, inside the month. The next new moon, 5 Feb, finds it in Makara and begins Magha.

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 6 Jan, with the Sun in Dhanu, began Pausha. This Shukla paksha reads Pausha in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 17 Mar 1980, 02:55 Mon. Since then the Sun has moved 303.4° round the stars. Vikram Samvat numbers that year 2037; Shaka Samvat numbers it 1902.