Panchang in Myshkin, Yaroslavl Oblast, Russia Sun 20 Jan 2019

Purnima follows the tithi at sunrise. Purnima begins at 11:49 on Sun 20 Jan, after that sunrise, and ends at 08:16 on Mon 21 Jan, before the next: it holds no sunrise. A tithi that holds no sunrise is kept on the day it is current: Sun 20 Jan. No text giving Purnima’s time was found; sunrise is Tithika’s convention.

Purnima: every date in Myshkin

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 156°–168° is the 14th, Shukla Chaturdashi. A day takes the tithi in force at its sunrise, 08:51 here. Trayodashi ended at 15:04 Sat, before it. Chaturdashi ends at 11:49, when the lead reaches 168°. The lead passed 0° at the new moon of 6 Jan, so the Moon is waxing: Shukla paksha.

A day takes the tithi in force at its sunrise. Purnima began at 11:49 and ended at 08:16 Mon, between the sunrises of 08:51 and 08:49 Mon. Sunday reads Chaturdashi and Monday reads Pratipada: Purnima is a kshaya tithi here.

The night of Sat 19 Jan ran from sunset 16:20 Sat to sunrise 08:51, 16 h 31 m. Cut into 15 muhurtas of 1 h 6 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 08:51 to 16:22, splits into 8 choghadiyas of 56 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 16:22 to 08:49 Mon, splits into 8 choghadiyas of 2 h 3 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 1 at 80°. It leaves at 02:52 Mon, for Pushya.

Add the Sun's and the Moon's places among the stars: 275.7° + 82° = 357.7°. The sum, cut into 27 parts of 13°20′, gives the yoga: 346°40′–360°00′ is the 27th, Vaidhriti. It ends at 12:11, then Vishkambha.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Chaturdashi is Garaja and the second Vanija. Garaja ended at 01:29, when the lead reached 162°; Vanija runs until 11:49.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 08:51 to 08:49 Mon, so the hours after midnight still belong to Raviwara.

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 2018, 16:11 Sat. Since then the Sun has moved 302.9° round the stars. Vikram Samvat numbers that year 2075; Shaka Samvat numbers it 1940.