Panchang in Ipameri, Goiás, Brazil Thu 28 Apr 1988

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 18:07 on Thu 28 Apr to 19:33 on Fri 29 Apr, touching pradosha on both evenings. The Nirnayasindhu takes the evening it holds more of: Thu 28 Apr. 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, 06:25 here. Ekadashi ended at 16:09 Wed, before it. Dwadashi ends at 18:07, when the lead reaches 144°. The lead passed 0° at the new moon of 16 Apr, so the Moon is waxing: Shukla paksha.

The night of Wed 27 Apr ran from sunset 17:55 Wed to sunrise 06:25, 12 h 30 m. Cut into 15 muhurtas of 50 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:25 to 17:54, 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 night here, 17:54 to 06:25 Fri, 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 fixed stars divide the Moon's path into 27 nakshatras of 13°20′, each in 4 padas of 3°20′. Uttara Phalguni spans 146°40′–160°00′; the Moon entered its pada 2 at 150°. It leaves at 19:55, for Hasta.

Add the Sun's and the Moon's places among the stars: 14.6° + 153.2° = 167.8°. The sum, cut into 27 parts of 13°20′, gives the yoga: 160°00′–173°20′ is the 13th, Vyaghata. It ends at 16:35, then Harshana.

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 05:11, when the lead reached 138°; Balava runs until 18:07.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:25 to 06:25 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: Mesha gives Vaishakha. The Sun enters Vrishabha on 14 May, inside the month. The next new moon, 15 May, finds it in Vrishabha and begins Jyeshtha.

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 16 Apr, with the Sun in Mesha, began Vaishakha. This Shukla paksha reads Vaishakha in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 17 Mar 1988, 23:02 Thu. Since then the Sun has moved 40.6° round the stars. Vikram Samvat numbers that year 2045; Shaka Samvat numbers it 1910.