Panchang in Davinópolis, Maranhão, Brazil Sun 18 Aug 2013

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 08:28 on Sun 18 Aug to 05:09 on Mon 19 Aug, so only Sunday’s pradosha (18:11–20:36) falls within it. No text giving Pradosh Vrat’s time was found; pradosha is Tithika’s convention.

Pradosh Vrat: every date in Davinópolis

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 132°–144° is the 12th, Shukla Dwadashi. A day takes the tithi in force at its sunrise, 06:15 here. Ekadashi ended at 11:38 Sat, before it. Dwadashi ends at 08:28, when the lead reaches 144°. The lead passed 0° at the new moon of 6 Aug, so the Moon is waxing: Shukla paksha.

A day takes the tithi in force at its sunrise. Trayodashi began at 08:28 and ended at 05:09 Mon, between the sunrises of 06:15 and 06:14 Mon. Sunday reads Dwadashi and Monday reads Chaturdashi: Trayodashi is a kshaya tithi here.

The night of Sat 17 Aug ran from sunset 18:11 Sat to sunrise 06:15, 12 h 4 m. Cut into 15 muhurtas of 48 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:15 to 18:11, 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, 18:11 to 06:14 Mon, 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′. Purva Ashadha spans 253°20′–266°40′; the Moon entered its pada 4 at 263°20′. It leaves at 10:08, for Uttara Ashadha.

Add the Sun's and the Moon's places among the stars: 121.5° + 264.3° = 385.8°, one full turn and 25.8°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 13°20′–26°40′ is the 2nd, Priti. It ends at 07:33, then Ayushmana.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Dwadashi is Bava and the second Balava. Bava ended at 22:05 Sat, when the lead reached 138°; Balava runs until 08:28.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:15 to 06:14 Mon, so the hours after midnight still belong to Raviwara.

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: Karka gives Shravana. The Sun enters Simha on 16 Aug, inside the month. The next new moon, 5 Sep, finds it in Simha and begins Bhadrapada.

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 6 Aug, with the Sun in Karka, began Shravana. This Shukla paksha reads Shravana in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 10 Apr 2013, 06:35 Wed. Since then the Sun has moved 124.9° round the stars. Vikram Samvat numbers that year 2070; Shaka Samvat numbers it 1935.