Panchang in Ipameri, Goiás, Brazil Thu 13 Sep 2012

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 03:29 on Thu 13 Sep to 02:39 on Fri 14 Sep, so only Thursday’s pradosha (18:07–20:31) 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: 324°–336° is the 28th, Krishna Trayodashi. A day takes the tithi in force at its sunrise, 06:09 here. Dwadashi ended at 03:29, before it. Trayodashi ends at 02:39 Fri, when the lead reaches 336°. The lead passed 180° at the full moon of 31 Aug, so the Moon is waning: Krishna paksha.

A day takes the tithi in force at its sunrise.

New Delhi · IST

Sunrise here, 06:05, came before Dwadashi ended at 11:59: this day reads Dwadashi.

Ipameri · UTC−3

Sunrise here, 06:09, came after Dwadashi ended at 03:29: this day reads Trayodashi.

The night of Wed 12 Sep ran from sunset 18:07 Wed to sunrise 06:09, 12 h 2 m. Cut into 15 muhurtas of 48 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:09 to 18:07, splits into 8 choghadiyas of 1 h 29 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 18:07 to 06:08 Fri, splits into 8 choghadiyas of 1 h 30 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′. Ashlesha spans 106°40′–120°00′; the Moon entered its pada 2 at 110°. It leaves at 19:57, for Magha.

Add the Sun's and the Moon's places among the stars: 146.9° + 112.3° = 259.2°. The sum, cut into 27 parts of 13°20′, gives the yoga: 253°20′–266°40′ is the 20th, Shiva. It ends at 18:34, then Siddha.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Trayodashi is Garaja and the second Vanija. Garaja runs until 15:09, when the lead reaches 330°; Vanija until 02:39 Fri.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:09 to 06:08 Fri, so the hours after midnight still belong to Guruwara.

A month normally holds one sankranti, the Sun's entry into a new rashi. From 17 Aug 12:54 Fri to 15 Sep 23:10 Sat the Sun stayed in Simha, entering Kanya at 16 Sep 09:24 Sun, after the new moon. A month with no sankranti is Adhika Bhadrapada, before Bhadrapada 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 15 Sep, with the Sun in Simha, begins Bhadrapada (Adhik). Until then this Krishna paksha reads Bhadrapada (Adhik) here, and Bhadrapada (Adhik) in the amanta count.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 22 Mar 2012, 11:37 Thu. Since then the Sun has moved 168.6° round the stars. Vikram Samvat numbers that year 2069; Shaka Samvat numbers it 1934.