Panchang in Ipameri, Goiás, Brazil Mon 20 Sep 2010

Shiva’s Pradosh puja is done in pradosha, the 3 muhurtas after sunset. Trayodashi runs from 23:02 on Sun 19 Sep to 01:33 on Tue 21 Sep, so only Monday’s pradosha (18:08–20:31) 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: 144°–156° is the 13th, Shukla Trayodashi. A day takes the tithi in force at its sunrise, 06:04 here. Dwadashi ended at 23:02 Sun, before it. Trayodashi ends at 01:33 Tue, when the lead reaches 156°. The lead passed 0° at the new moon of 8 Sep, so the Moon is waxing: Shukla paksha.

A day takes the tithi in force at its sunrise.

New Delhi · IST

Sunrise here, 06:08, came before Dwadashi ended at 07:32: this day reads Dwadashi.

Ipameri · UTC−3

Sunrise here, 06:04, came after Dwadashi ended at 23:02 Sun: this day reads Trayodashi.

The night of Sun 19 Sep ran from sunset 18:08 Sun to sunrise 06:04, 11 h 56 m. Cut into 15 muhurtas of 47 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:04 to 18:08, 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 night here, 18:08 to 06:03 Tue, 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 fixed stars divide the Moon's path into 27 nakshatras of 13°20′, each in 4 padas of 3°20′. Dhanishtha spans 293°20′–306°40′; the Moon entered its pada 3 at 300°. It leaves at 18:37, for Shatabhisha.

Add the Sun's and the Moon's places among the stars: 153.3° + 300.5° = 453.8°, one full turn and 93.8°. Past the turn, cut into 27 parts of 13°20′, it gives the yoga: 93°20′–106°40′ is the 8th, Dhriti. It ends at 06:12 Tue, then Shula.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Trayodashi is Kaulava and the second Taitila. Kaulava runs until 12:18, when the lead reaches 150°; Taitila until 01:33 Tue.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:04 to 06:03 Tue, so the hours after midnight still belong to Somawara.

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: Simha gives Bhadrapada. The Sun enters Kanya on 16 Sep, inside the month. The next new moon, 7 Oct, finds it in Kanya and begins Ashwina.

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 Sep, with the Sun in Simha, began Bhadrapada. This Shukla paksha reads Bhadrapada in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 15 Mar 2010, 18:01 Mon. Since then the Sun has moved 182.1° round the stars. Vikram Samvat numbers that year 2067; Shaka Samvat numbers it 1932.