Panchang in Thazhecode, Kerala Sat 20 Jul 2013

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 10:49 on Sat 20 Jul to 07:16 on Sun 21 Jul, so only Saturday’s pradosha (18:53–21:08) falls within it. No text giving Pradosh Vrat’s time was found; pradosha is Tithika’s convention.

Pradosh Vrat: every date in Thazhecode

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, 06:11 here. Ekadashi ended at 14:00 Fri, before it. Dwadashi ends at 10:49, when the lead reaches 144°. The lead passed 0° at the new moon of 8 Jul, so the Moon is waxing: Shukla paksha.

The night of Fri 19 Jul ran from sunset 18:53 Fri to sunrise 06:11, 11 h 18 m. Cut into 15 muhurtas of 45 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:11 to 18:53, splits into 8 choghadiyas of 1 h 35 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 18:53 to 06:11 Sun, splits into 8 choghadiyas of 1 h 24 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 3 at 233°20′. It leaves at 14:38, for Mula.

Add the Sun's and the Moon's places among the stars: 93.4° + 234.7° = 328.1°. The sum, cut into 27 parts of 13°20′, gives the yoga: 320°00′–333°20′ is the 25th, Brahma. It ends at 13:58, then Indra.

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 00:27, when the lead reached 138°; Balava runs until 10:49.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:11 to 06:11 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: Mithuna gives Ashadha. The Sun enters Karka on 16 Jul, inside the month. The next new moon, 7 Aug, finds it in Karka and begins Shravana.

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 8 Jul, with the Sun in Mithuna, began Ashadha. This Shukla paksha reads Ashadha in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 10 Apr 2013, 15:05 Wed. Since then the Sun has moved 96.8° round the stars. Vikram Samvat numbers that year 2070; Shaka Samvat numbers it 1935.