Panchang in Ipameri, Goiás, Brazil Sat 17 Jan 2015

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 19:37 on Sat 17 Jan to 17:20 on Sun 18 Jan, so only Saturday’s pradosha (19:54–22:05) 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, 06:51 here. Ekadashi ended at 21:09 Fri, before it. Dwadashi ends at 19:37, when the lead reaches 324°. The lead passed 180° at the full moon of 5 Jan, so the Moon is waning: Krishna paksha.

The night of Fri 16 Jan ran from sunset 19:54 Fri to sunrise 06:51, 10 h 57 m. Cut into 15 muhurtas of 43 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:51 to 19:54, splits into 8 choghadiyas of 1 h 37 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 19:54 to 06:51 Sun, splits into 8 choghadiyas of 1 h 22 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′. Jyeshtha spans 226°40′–240°00′; the Moon entered its pada 1 at 226°40′. It leaves at 00:04 Sun, for Mula.

Add the Sun's and the Moon's places among the stars: 272.8° + 229.9° = 502.7°, one full turn and 142.7°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 133°20′–146°40′ is the 11th, Vriddhi. It ends at 13:04, then Dhruva.

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 08:29, when the lead reaches 318°; Taitila until 19:37.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:51 to 06:51 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: Dhanu gives Pausha. The Sun enters Makara on 14 Jan, inside the month. The next new moon, 20 Jan, finds it in Makara and begins Magha.

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 20 Jan, with the Sun in Makara, begins Magha. Until then this Krishna paksha reads Magha here, and Pausha in the amanta count.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 30 Mar 2014, 15:44 Sun. Since then the Sun has moved 286.9° round the stars. Vikram Samvat numbers that year 2071; Shaka Samvat numbers it 1936.