Panchang in Ipameri, Goiás, Brazil Mon 29 Jul 1985

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 23:12 on Sun 28 Jul to 21:23 on Mon 29 Jul, so only Monday’s pradosha (17:58–20:30) 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: 144°–156° is the 13th, Shukla Trayodashi. A day takes the tithi in force at its sunrise, 06:40 here. Dwadashi ended at 23:12 Sun, before it. Trayodashi ends at 21:23, when the lead reaches 156°. The lead passed 0° at the new moon of 17 Jul, so the Moon is waxing: Shukla paksha.

A day takes the tithi in force at its sunrise.

New Delhi · IST

Sunrise here, 05:40, came before Dwadashi ended at 07:42: this day reads Dwadashi.

Ipameri · UTC−3

Sunrise here, 06:40, came after Dwadashi ended at 23:12 Sun: this day reads Trayodashi.

The night of Sun 28 Jul ran from sunset 17:57 Sun to sunrise 06:40, 12 h 43 m. Cut into 15 muhurtas of 50 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:40 to 17:58, splits into 8 choghadiyas of 1 h 24 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 17:58 to 06:39 Tue, splits into 8 choghadiyas of 1 h 35 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′. Mula spans 240°00′–253°20′; the Moon entered its pada 4 at 250°. It leaves at 11:21, for Purva Ashadha.

Add the Sun's and the Moon's places among the stars: 102.6° + 250.6° = 353.2°. The sum, cut into 27 parts of 13°20′, gives the yoga: 346°40′–360°00′ is the 27th, Vaidhriti. It ends at 17:40, then Vishkambha.

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 runs until 10:16, when the lead reaches 150°; Taitila until 21:23.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:40 to 06:39 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 17 Jul 20:56 Wed to 16 Aug 07:05 Fri the Sun stayed in Karka, entering Simha at 16 Aug 11:23 Fri, after the new moon. A month with no sankranti is Adhika Shravana, before Shravana 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 17 Jul, with the Sun in Karka, began Shravana (Adhik). This Shukla paksha reads Shravana (Adhik) in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 21 Mar 1985, 08:58 Thu. Since then the Sun has moved 125.4° round the stars. Vikram Samvat numbers that year 2042; Shaka Samvat numbers it 1907.