Panchang in Ipameri, Goiás, Brazil Tue 10 Jul 2018

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 10:15 on Tue 10 Jul to 07:04 on Wed 11 Jul, so only Tuesday’s pradosha (17:52–20:26) 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, 06:44 here. Ekadashi ended at 12:57 Mon, before it. Dwadashi ends at 10:15, when the lead reaches 324°. The lead passed 180° at the full moon of 28 Jun, so the Moon is waning: Krishna paksha.

The night of Mon 9 Jul ran from sunset 17:51 Mon to sunrise 06:44, 12 h 53 m. Cut into 15 muhurtas of 51 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:44 to 17:52, splits into 8 choghadiyas of 1 h 23 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 17:52 to 06:44 Wed, splits into 8 choghadiyas of 1 h 36 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′. Rohini spans 40°00′–53°20′; the Moon entered its pada 2 at 43°20′. It leaves at 18:45, for Mrigashira.

Add the Sun's and the Moon's places among the stars: 84° + 46° = 130°. The sum, cut into 27 parts of 13°20′, gives the yoga: 120°00′–133°20′ is the 10th, Ganda. It ends at 11:54, then Vriddhi.

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 ended at 23:40 Mon, when the lead reached 318°; Taitila runs until 10:15.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:44 to 06:44 Wed, so the hours after midnight still belong to Mangalawara.

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: Vrishabha gives Jyeshtha. The Sun enters Mithuna on 15 Jun, inside the month. The next new moon, 12 Jul, finds it in Mithuna and begins Ashadha.

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 12 Jul, with the Sun in Mithuna, begins Ashadha. Until then this Krishna paksha reads Ashadha here, and Jyeshtha in the amanta count.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 17 Mar 2018, 10:11 Sat. Since then the Sun has moved 111.2° round the stars. Vikram Samvat numbers that year 2075; Shaka Samvat numbers it 1940.