Panchang in Chahārbāgh, Alborz Province, Iran Tue 19 Jul 2016

Guru Purnima follows the tithi at sunrise. Purnima runs from 03:40 on Tue 19 Jul to 03:26 on Wed 20 Jul, so it holds sunrise only on Tue 19 Jul, at 06:04. No text giving Guru Purnima’s time was found; sunrise is Tithika’s convention.

Guru Purnima: every date in Chahārbāgh

Purnima follows the tithi at sunrise. Purnima runs from 03:40 on Tue 19 Jul to 03:26 on Wed 20 Jul, so it holds sunrise only on Tue 19 Jul, at 06:04. No text giving Purnima’s time was found; sunrise is Tithika’s convention.

Purnima: every date in Chahārbāgh

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 168°–180° is the 15th, Shukla Purnima. A day takes the tithi in force at its sunrise, 06:04 here. Chaturdashi ended at 03:40, before it. Purnima ends at 03:26 Wed, when the lead reaches 180°. The lead passed 0° at the new moon of 4 Jul, so the Moon is waxing: Shukla paksha.

The night of Mon 18 Jul ran from sunset 20:21 Mon to sunrise 06:04, 9 h 43 m. Cut into 15 muhurtas of 38 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 06:04 to 20:20, splits into 8 choghadiyas of 1 h 47 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 20:20 to 06:05 Wed, splits into 8 choghadiyas of 1 h 13 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 3 at 260°. It leaves at 14:47, for Uttara Ashadha.

Add the Sun's and the Moon's places among the stars: 92.7° + 261.9° = 354.6°. The sum, cut into 27 parts of 13°20′, gives the yoga: 346°40′–360°00′ is the 27th, Vaidhriti. It ends at 15:13, then Vishkambha.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Purnima is Vishti and the second Bava. Vishti runs until 15:37, when the lead reaches 174°; Bava until 03:26 Wed.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 06:04 to 06:05 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: Mithuna gives Ashadha. The Sun enters Karka on 16 Jul, inside the month. The next new moon, 3 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 4 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: 7 Apr 2016, 15:53 Thu. Since then the Sun has moved 98.7° round the stars. Vikram Samvat numbers that year 2073; Shaka Samvat numbers it 1938.