Onam (Thiruvonam) across India

1. The month is the Malayalam solar month of sidereal Simha (Leo): it begins on the day the Sun enters Simha (Leo) by the Kerala rule (before 3/5 of the daytime has passed, the end of Madhyahna, else the next day) and ends on the day before the next month begins.
2. Shravana belongs to the day at whose sunrise it prevails for at least 6 nazhikas (6/60 of the day, about 2 hours 24 minutes); if it lasts less than that after sunrise, it belongs to the previous day, on which it began; if it touches no sunrise, to the day that contains it.
3. If the month has two Shravana days, the later one is taken: the first comes so early that the first day of the festival, Atham, would fall in the previous month.
4. Sidereal positions use the ayanamsa of your calculation profile; a different ayanamsa can shift the moment by several minutes.

When Chingam contains two Thiruvonams (the first then falls in its first five days, with its Atham, the first day of the ten-day festival, in Karkidakam), Onam is kept on the second, e.g. 15 September 2024; the first is shown as not selected. Kerala panchangs can differ on the nakshatra-day threshold (6 nazhikas after sunrise is used here); verify with a Kerala panchang in borderline years.

Onam (Thiruvonam)