Panchang in Sevan, Gegharkunik, Armenia Sat 19 Apr 1913

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, 05:16 here. Dwadashi ended at 09:21 Fri, before it. Trayodashi ends at 06:19, when the lead reaches 156°. The lead passed 0° at the new moon of 6 Apr, so the Moon is waxing: Shukla paksha.

A day takes the tithi in force at its sunrise. Chaturdashi began at 06:19 and ended at 03:20 Sun, between the sunrises of 05:16 and 05:15 Sun. Saturday reads Trayodashi and Sunday reads Purnima: Chaturdashi is a kshaya tithi here.

The night of Fri 18 Apr ran from sunset 18:41 Fri to sunrise 05:16, 10 h 35 m. Cut into 15 muhurtas of 42 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 05:16 to 18:42, splits into 8 choghadiyas of 1 h 40 m. Their names follow a fixed order that starts from the weekday, and each name is counted good, neutral or bad.

The night here, 18:42 to 05:15 Sun, splits into 8 choghadiyas of 1 h 19 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′. Hasta spans 160°00′–173°20′; the Moon entered its pada 1 at 160°. It leaves at 01:08 Sun, for Chitra.

Add the Sun's and the Moon's places among the stars: 5.8° + 161.2° = 167°. The sum, cut into 27 parts of 13°20′, gives the yoga: 160°00′–173°20′ is the 13th, Vyaghata. It ends at 15:02, then Harshana.

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 ended at 19:50 Fri, when the lead reached 150°; Taitila runs until 06:19.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 05:16 to 05:15 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: Meena gives Chaitra. The Sun enters Mesha on 13 Apr, inside the month. The next new moon, 6 May, finds it in Mesha and begins Vaishakha.

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 Apr, with the Sun in Meena, began Chaitra. This Shukla paksha reads Chaitra in both counts.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 6 Apr 1913, 20:47 Sun. Since then the Sun has moved 12.1° round the stars. Vikram Samvat numbers that year 1970; Shaka Samvat numbers it 1835.