Panchang in Ipameri, Goiás, Brazil Mon 10 Dec 2012

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 17:22 on Mon 10 Dec to 14:02 on Tue 11 Dec, so only Monday’s pradosha (19:40–21:50) 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: 312°–324° is the 27th, Krishna Dwadashi. A day takes the tithi in force at its sunrise, 06:30 here. Ekadashi ended at 20:16 Sun, before it. Dwadashi ends at 17:22, when the lead reaches 324°. The lead passed 180° at the full moon of 28 Nov, so the Moon is waning: Krishna paksha.

The night of Sun 9 Dec ran from sunset 19:40 Sun to sunrise 06:30, 10 h 50 m. Cut into 15 muhurtas of 43 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:30 to 19:40, splits into 8 choghadiyas of 1 h 38 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 19:40 to 06:31 Tue, splits into 8 choghadiyas of 1 h 21 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′. Swati spans 186°40′–200°00′; the Moon entered its pada 2 at 190°. It leaves at 18:48, for Vishakha.

Add the Sun's and the Moon's places among the stars: 234.6° + 192.4° = 427°, one full turn and 67°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 66°40′–80°00′ is the 6th, Atiganda. It ends at 02:05 Tue, then Sukarma.

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 runs until 06:52, when the lead reaches 318°; Taitila until 17:22.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:30 to 06:31 Tue, so the hours after midnight still belong to Somawara.

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: Tula gives Kartika. The Sun enters Vrishchika on 15 Nov, inside the month. The next new moon, 13 Dec, finds it in Vrishchika and begins Margashirsha.

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 13 Dec, with the Sun in Vrishchika, begins Margashirsha. Until then this Krishna paksha reads Margashirsha here, and Kartika 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 256.3° round the stars. Vikram Samvat numbers that year 2069; Shaka Samvat numbers it 1934.