Panchang in Codcod, Western Visayas, Philippines Mon 12 Aug 2013

Nag Panchami follows the tithi at sunrise. Panchami runs from 09:22 on Sun 11 Aug to 09:15 on Mon 12 Aug, so it holds sunrise only on Mon 12 Aug, at 05:37. No text giving Nag Panchami’s time was found; sunrise is Tithika’s convention.

Nag Panchami: every date in Codcod

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 48°–60° is the 5th, Shukla Panchami. A day takes the tithi in force at its sunrise, 05:37 here. Chaturthi ended at 09:22 Sun, before it. Panchami ends at 09:15, when the lead reaches 60°. The lead passed 0° at the new moon of 7 Aug, so the Moon is waxing: Shukla paksha.

The night of Sun 11 Aug ran from sunset 18:07 Sun to sunrise 05:37, 11 h 30 m. Cut into 15 muhurtas of 46 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 05:37 to 18:07, splits into 8 choghadiyas of 1 h 33 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 18:07 to 05:37 Tue, splits into 8 choghadiyas of 1 h 26 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′. Chitra spans 173°20′–186°40′; the Moon entered its pada 1 at 173°20′. It leaves at 05:35 Tue, for Swati.

Add the Sun's and the Moon's places among the stars: 115.3° + 173.5° = 288.8°. The sum, cut into 27 parts of 13°20′, gives the yoga: 280°00′–293°20′ is the 22nd, Sadhya. It ends at 13:21, then Shubha.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Panchami is Bava and the second Balava. Bava ended at 21:22 Sun, when the lead reached 54°; Balava runs until 09:15.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 05:37 to 05:37 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: Karka gives Shravana. The Sun enters Simha on 17 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 7 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, 17:35 Wed. Since then the Sun has moved 118.7° round the stars. Vikram Samvat numbers that year 2070; Shaka Samvat numbers it 1935.