Panchang in Davinópolis, Maranhão, Brazil Sun 18 Jan 1981

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, 06:08 here. Dwadashi ended at 09:19 Sat, before it. Trayodashi ends at 07:25, when the lead reaches 156°. 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. Chaturdashi began at 07:25 and ended at 05:49 Mon, between the sunrises of 06:08 and 06:08 Mon. Sunday reads Trayodashi and Monday reads Purnima: Chaturdashi is a kshaya tithi here.

The night of Sat 17 Jan ran from sunset 18:31 Sat to sunrise 06:08, 11 h 37 m. Cut into 15 muhurtas of 46 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:08 to 18:32, 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 night here, 18:32 to 06:08 Mon, 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 fixed stars divide the Moon's path into 27 nakshatras of 13°20′, each in 4 padas of 3°20′. Ardra spans 66°40′–80°00′; the Moon entered its pada 1 at 66°40′. It leaves at 23:32, for Punarvasu.

Add the Sun's and the Moon's places among the stars: 274.6° + 69.9° = 344.5°. The sum, cut into 27 parts of 13°20′, gives the yoga: 333°20′–346°40′ is the 26th, Indra. It ends at 09:33, then Vaidhriti.

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 ended at 20:20 Sat, when the lead reached 150°; Taitila runs until 07:25.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:08 to 06:08 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 13 Jan, inside the month. The next new moon, 4 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: 16 Mar 1980, 15:55 Sun. Since then the Sun has moved 301.8° round the stars. Vikram Samvat numbers that year 2037; Shaka Samvat numbers it 1902.