01What Amavasya is
Amavasya is the new moon, the last tithi of the dark half, Krishna paksha, when the Moon stands closest to the Sun and cannot be seen at all. It comes once a lunar month, twelve or thirteen times a year, and in the amanta calendars of South and West India it closes the month. The tradition gives Amavasya to the pitri, the ancestors of the family, more than to any one deity, and several named days fall on it: Somvati and Shani Amavasya by weekday, Mauni Amavasya in winter, Sarva Pitru Amavasya at the end of Pitru Paksha, and the Lakshmi puja of Diwali.
02How the day and time are worked out
This page lists each Amavasya on the day the new moon tithi holds at sunrise, which is how the panchangs date the day for snan, daan and tarpan. The tithi often begins in the middle of one day and ends during the next, so each entry also gives the moment it begins and the moment it ends: rites that belong to the tithi itself, such as shraddha in the afternoon, are timed inside that span. An Amavasya that touches no sunrise at all is kept on the day it begins. The weekday of the chosen day decides whether it is also a Somvati or a Shani Amavasya.
03How it is kept
The central act of Amavasya is tarpan: water mixed with black sesame, offered from cupped hands to the pitri, usually facing south, with the names of the family line where they are known. Many households cook a plain meal for the ancestors and set a portion aside for a cow, a crow and a dog before anyone eats. A river bath in the morning, charity of food or clothes, and a lamp under a peepal tree in the evening are widely kept. The tradition holds Amavasya unsuited to beginnings, so many families put off a journey, a purchase or a new venture to another day.
04The rest of the calendar
