Panchang in Ipameri, Goiás, Brazil Thu 13 Oct 1921

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 15:42 on Thu 13 Oct to 17:35 on Fri 14 Oct, so only Thursday’s pradosha (18:12–20:31) falls within it. No text giving Pradosh Vrat’s time was found; pradosha is Tithika’s convention.

Pradosh Vrat: every date in Ipameri

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, 05:45 here. Ekadashi ended at 13:27 Wed, before it. Dwadashi ends at 15:42, when the lead reaches 144°. The lead passed 0° at the new moon of 1 Oct, so the Moon is waxing: Shukla paksha.

The night of Wed 12 Oct ran from sunset 18:12 Wed to sunrise 05:45, 11 h 33 m. Cut into 15 muhurtas of 46 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 05:45 to 18:12, 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, 18:12 to 05:45 Fri, splits into 8 choghadiyas of 1 h 26 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′. Shatabhisha spans 306°40′–320°00′; the Moon entered its pada 3 at 313°20′. It leaves at 13:27, for Purva Bhadrapada.

Add the Sun's and the Moon's places among the stars: 176.7° + 316.1° = 492.8°, one full turn and 132.8°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 120°00′–133°20′ is the 10th, Ganda. It ends at 06:38, then Vriddhi.

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 02:37, when the lead reached 138°; Balava runs until 15:42.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 05:45 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: Kanya gives Ashwina. The Sun enters Tula on 16 Oct, inside the month. The next new moon, 30 Oct, finds it in Tula and begins Kartika.

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 Oct, with the Sun in Kanya, began Ashwina. This Shukla paksha reads Ashwina in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 8 Apr 1921, 06:04 Fri. Since then the Sun has moved 181.5° round the stars. Vikram Samvat numbers that year 1978; Shaka Samvat numbers it 1843.