Panchang in Sevan, Gegharkunik, Armenia Sun 10 May 1964

Shiva’s worship centres on nishitha, the midnight muhurta. Chaturdashi runs from 07:52 on Sun 10 May to 04:35 on Mon 11 May, so only Sunday night’s nishitha (00:36 Mon–01:15 Mon) falls within it. No text giving Masik Shivratri’s time was found; nishitha is Tithika’s convention.

Masik Shivratri: every date in Sevan

The Moon gains on the Sun about 12° a day. Each 12° of lead is one tithi: 324°–336° is the 28th, Krishna Trayodashi. A day takes the tithi in force at its sunrise, 05:48 here. Dwadashi ended at 10:41 Sat, before it. Trayodashi ends at 07:52, when the lead reaches 336°. The lead passed 180° at the full moon of 26 Apr, so the Moon is waning: Krishna paksha.

A day takes the tithi in force at its sunrise. Chaturdashi began at 07:52 and ended at 04:35 Mon, between the sunrises of 05:48 and 05:47 Mon. Sunday reads Trayodashi and Monday reads Amavasya: Chaturdashi is a kshaya tithi here.

The night of Sat 9 May ran from sunset 20:03 Sat to sunrise 05:48, 9 h 45 m. Cut into 15 muhurtas of 39 m, its 14th is Brahma Muhurta, the one before the last.

Daylight here, 05:48 to 20:04, 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, 20:04 to 05:47 Mon, splits into 8 choghadiyas of 1 h 12 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′. Ashwini spans 0°00′–13°20′; the Moon entered its pada 1 at 0°. It leaves at 01:55 Mon, for Bharani.

Add the Sun's and the Moon's places among the stars: 26.1° + 0.9° = 27°. The sum, cut into 27 parts of 13°20′, gives the yoga: 26°40′–40°00′ is the 3rd, Ayushmana. It ends at 01:35 Mon, then Saubhagya.

A karana is half a tithi: 6° of the Moon's lead, so the first half of Trayodashi is Garaja and the second Vanija. Garaja ended at 21:20 Sat, when the lead reached 330°; Vanija runs until 07:52.

A Hindu day runs from one sunrise to the next, not midnight to midnight. This one runs 05:48 to 05:47 Mon, so the hours after midnight still belong to Raviwara.

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, 12 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 12 May, with the Sun in Mesha, begins Vaishakha. Until then this Krishna paksha reads Vaishakha here, and Chaitra in the amanta count.

A samvat year begins with Chaitra, the month whose new moon finds the Sun in Meena: 14 Mar 1964, 06:13 Sat. Since then the Sun has moved 55.9° round the stars. Vikram Samvat numbers that year 2021; Shaka Samvat numbers it 1886.