2000
- Thursday, 6 January 2000 · Margashirsha Amavasya
- Saturday, 5 February 2000 · Mauni Amavasya (Shani)
- Monday, 6 March 2000 · Magha Amavasya (Somvati)
- Tuesday, 4 April 2000 · Phalguna Amavasya (Bhaumvati)
- Thursday, 4 May 2000 · Chaitra Amavasya
- Friday, 2 June 2000 · Vat Savitri Amavasya
- Saturday, 1 July 2000 · Jyeshtha Amavasya (Shani)
- Monday, 31 July 2000 · Hariyali Amavasya (Somvati)
- Tuesday, 29 August 2000 · Shravana Amavasya (Bhaumvati)
- Wednesday, 27 September 2000 · Mahalaya / Sarvapitri Amavasya
- Friday, 27 October 2000 · Diwali (Lakshmi Puja) Amavasya
- Saturday, 25 November 2000 · Kartika Amavasya (Shani)
- Monday, 25 December 2000 · Margashirsha Amavasya (Somvati)
2001
- Wednesday, 24 January 2001 · Mauni Amavasya
- Friday, 23 February 2001 · Magha Amavasya
- Saturday, 24 March 2001 · Phalguna Amavasya (Shani)
- Monday, 23 April 2001 · Chaitra Amavasya (Somvati)
- Wednesday, 23 May 2001 · Vat Savitri Amavasya
- Thursday, 21 June 2001 · Jyeshtha Amavasya
- Friday, 20 July 2001 · Hariyali Amavasya
- Sunday, 19 August 2001 · Shravana Amavasya
- Monday, 17 September 2001 · Mahalaya / Sarvapitri Amavasya (Somvati)
- Tuesday, 16 October 2001 · Adhika Ashwina Amavasya (Bhaumvati)
- Thursday, 15 November 2001 · Diwali (Lakshmi Puja) Amavasya
- Friday, 14 December 2001 · Kartika Amavasya
How the date is fixed
Every new-moon day, taken as the day on which Amavasya is running at sunrise. One that falls on a Monday is called Somvati, on a Tuesday Bhaumvati, and on a Saturday Shani Amavasya. Amavasya ends the dark half, so both month names are given.
About
Amavasya is the tithi in which the Moon's longitude returns to the Sun's, closing the dark half and, in amanta reckoning, the month itself. It is the tithi of the pitris, and tarpana for ancestors is its regular observance; the aparahna (afternoon) is the governing period for shraddha, so the day whose afternoon carries Amavasya is chosen. Several named Amavasyas stand out: Sarva Pitru Amavasya ending Pitru Paksha, Diwali on Ashwina Amavasya, Mauni Amavasya in Pausha, and any Amavasya on a Monday (Somvati) or Saturday (Shani). Solar eclipses can only occur on Amavasya, which is why eclipse rules are tied to it.
How it is observed
Tarpana for ancestors in the afternoon, river bathing on Somvati and Mauni Amavasya, and lamps at dusk.