Panchang in Ipameri, Goiás, Brazil Sat 18 Feb 2012

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 21:08 on Sat 18 Feb to 20:34 on Sun 19 Feb, touching pradosha on both evenings. The Nirnayasindhu takes the evening it holds more of: Sat 18 Feb. 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, 07:07 here. Ekadashi ended at 21:59 Fri, before it. Dwadashi ends at 21:08, when the lead reaches 324°. The lead passed 180° at the full moon of 7 Feb, so the Moon is waning: Krishna paksha.

The night of Fri 17 Feb ran from sunset 19:45 Fri to sunrise 07:07, 11 h 22 m. Cut into 15 muhurtas of 45 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 07:07 to 19:45, 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 night here, 19:45 to 07:08 Sun, 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 fixed stars divide the Moon's path into 27 nakshatras of 13°20′, each in 4 padas of 3°20′. Purva Ashadha spans 253°20′–266°40′; the Moon entered its pada 3 at 260°. It leaves at 15:45, for Uttara Ashadha.

Add the Sun's and the Moon's places among the stars: 305.1° + 261.8° = 566.9°, one full turn and 206.9°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 200°00′–213°20′ is the 16th, Siddhi. It ends at 17:47, then Vyatipata.

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 09:31, when the lead reaches 318°; Taitila until 21:08.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 07:07 to 07:08 Sun, so the hours after midnight still belong to Shaniwara.

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: Makara gives Magha. The Sun enters Kumbha on 13 Feb, inside the month. The next new moon, 21 Feb, finds it in Kumbha and begins Phalguna.

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 21 Feb, with the Sun in Kumbha, begins Phalguna. Until then this Krishna paksha reads Phalguna here, and Magha in the amanta count.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 3 Apr 2011, 11:32 Sun. Since then the Sun has moved 315.6° round the stars. Vikram Samvat numbers that year 2068; Shaka Samvat numbers it 1933.