Panchang in Ipameri, Goiás, Brazil Mon 10 May 1915

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 17:59 on Mon 10 May to 19:58 on Tue 11 May, touching pradosha on both evenings. The Nirnayasindhu takes the evening it holds more of: Mon 10 May. 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: 312°–324° is the 27th, Krishna Dwadashi. A day takes the tithi in force at its sunrise, 06:28 here. Ekadashi ended at 16:18 Sun, before it. Dwadashi ends at 17:59, when the lead reaches 324°. The lead passed 180° at the full moon of 29 Apr, so the Moon is waning: Krishna paksha.

The night of Sun 9 May ran from sunset 17:50 Sun to sunrise 06:28, 12 h 38 m. Cut into 15 muhurtas of 50 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:28 to 17:49, splits into 8 choghadiyas of 1 h 25 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 17:49 to 06:28 Tue, splits into 8 choghadiyas of 1 h 34 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′. Uttara Bhadrapada spans 333°20′–346°40′; the Moon entered its pada 4 at 343°20′. It leaves at 10:32, for Revati.

Add the Sun's and the Moon's places among the stars: 26° + 344.6° = 370.6°, one full turn and 10.6°. 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 11:31, then Priti.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Dwadashi is Kaulava and the second Taitila. Kaulava ended at 05:05, when the lead reached 318°; Taitila runs until 17:59.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:28 to 06:28 Tue, so the hours after midnight still belong to Somawara.

A month normally holds one sankranti, the Sun's entry into a new rashi. From 14 Apr 08:35 Wed to 14 May 00:30 Fri the Sun stayed in Mesha, entering Vrishabha at 14 May 10:42 Fri, after the new moon. A month with no sankranti is Adhika Vaishakha, before Vaishakha itself.

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 14 May, with the Sun in Mesha, begins Vaishakha (Adhik). Until then this Krishna paksha reads Vaishakha (Adhik) here, and Vaishakha (Adhik) in the amanta count.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 15 Mar 1915, 16:41 Mon. Since then the Sun has moved 54.5° round the stars. Vikram Samvat numbers that year 1972; Shaka Samvat numbers it 1837.