2008
- Tuesday, 8 January 2008 · Margashirsha Amavasya (Bhaumvati)
- Thursday, 7 February 2008 · Mauni Amavasya
- Friday, 7 March 2008 · Magha Amavasya
- Sunday, 6 April 2008 · Phalguna Amavasya
- Monday, 5 May 2008 · Chaitra Amavasya (Somvati)
- Tuesday, 3 June 2008 · Vat Savitri Amavasya (Bhaumvati)
- Thursday, 3 July 2008 · Jyeshtha Amavasya
- Friday, 1 August 2008 · Hariyali Amavasya
- Saturday, 30 August 2008 · Shravana Amavasya (Shani)
- Monday, 29 September 2008 · Mahalaya / Sarvapitri Amavasya (Somvati)
- Tuesday, 28 October 2008 · Diwali (Lakshmi Puja) Amavasya (Bhaumvati)
- Thursday, 27 November 2008 · Kartika Amavasya
- Saturday, 27 December 2008 · Margashirsha Amavasya (Shani)
2009
- Monday, 26 January 2009 · Mauni Amavasya (Somvati)
- Tuesday, 24 February 2009 · Magha Amavasya (Bhaumvati)
- Thursday, 26 March 2009 · Phalguna Amavasya
- Saturday, 25 April 2009 · Chaitra Amavasya (Shani)
- Sunday, 24 May 2009 · Vat Savitri Amavasya
- Monday, 22 June 2009 · Jyeshtha Amavasya (Somvati)
- Wednesday, 22 July 2009 · Hariyali Amavasya
- Thursday, 20 August 2009 · Shravana Amavasya
- Friday, 18 September 2009 · Mahalaya / Sarvapitri Amavasya
- Sunday, 18 October 2009 · Diwali (Lakshmi Puja) Amavasya
- Monday, 16 November 2009 · Kartika Amavasya (Somvati)
- Wednesday, 16 December 2009 · Margashirsha 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.