Thai Amavasya or Thai Amavasai is the No Moon day in Thai month in Tamil calendar. In 2013, Thai Amavasya date is February 10.
Though on every amavasai, devotees offer Tharpanam to their dead ancestors, Thai amavasai is even more auspicious as it is the first Amavasya in Utharayanam.
Thai Amavasya is also known for Punya snana in Rameshwaram, Srirangam, Tiruchendur, and some other famous pilgrimages.
Thai Amavasya falls on Poushya Amavasya in Marathi, Gujarati, Kannada, and Telugu calendars; and on Magh Amavasya in North Indian Hindi calendars. It is also celebrated as Mauni Amavasya.
It is to note that the first day of Thai month is celebrated as Thai Pongal and Thai Pournami is celebrated as Thaipusam.
Thai Amavasya 2012 date was January 23. In 2012, it starts at 2.20 Pm on 22nd January and ends at 1.10 pm on 23 January 2012 according to standard Tamil Panchangam.