Panchang in Davinópolis, Maranhão, Brazil Sat 13 Feb 1965

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 08:25 on Sat 13 Feb to 05:08 on Sun 14 Feb, so only Saturday’s pradosha (19:32–21:53) falls within it. No text giving Pradosh Vrat’s time was found; pradosha is Tithika’s convention.

Pradosh Vrat: every date in Davinópolis

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 132°–144° is the 12th, Shukla Dwadashi. A day takes the tithi in force at its sunrise, 07:15 here. Ekadashi ended at 11:29 Fri, before it. Dwadashi ends at 08:25, when the lead reaches 144°. The lead passed 0° at the new moon of 1 Feb, so the Moon is waxing: Shukla paksha.

A day takes the tithi in force at its sunrise. Trayodashi began at 08:25 and ended at 05:08 Sun, between the sunrises of 07:15 and 07:15 Sun. Saturday reads Dwadashi and Sunday reads Chaturdashi: Trayodashi is a kshaya tithi here.

The night of Fri 12 Feb ran from sunset 19:32 Fri to sunrise 07:15, 11 h 43 m. Cut into 15 muhurtas of 46 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 07:15 to 19:32, splits into 8 choghadiyas of 1 h 32 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 19:32 to 07:15 Sun, 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′. Punarvasu spans 80°00′–93°20′; the Moon entered its pada 2 at 83°20′. It leaves at 21:36, for Pushya.

Add the Sun's and the Moon's places among the stars: 301.1° + 84.4° = 385.5°, one full turn and 25.5°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 13°20′–26°40′ is the 2nd, Priti. It ends at 08:58, then Ayushmana.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Dwadashi is Bava and the second Balava. Bava ended at 21:59 Fri, when the lead reached 138°; Balava runs until 08:25.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 07:15 to 07:15 Sun, so the hours after midnight still belong to Shaniwara.

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: Makara gives Magha. The Sun enters Kumbha on 12 Feb, inside the month. The next new moon, 3 Mar, finds it in Kumbha and begins Phalguna.

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 1 Feb, with the Sun in Makara, began Magha. This Shukla paksha reads Magha in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 13 Mar 1964, 23:13 Fri. Since then the Sun has moved 330.9° round the stars. Vikram Samvat numbers that year 2021; Shaka Samvat numbers it 1886.