Thiruvathira

Thiruvathirai or Thiruvathira or Arudhra Darisanam (Malayalam: തിരുവാതിര, Tamil: திருவாதிரை) is a Hindu festival celebrated in the South Indian states of Kerala and Tamil Nadu. Thiruvathirai(Arudhra) in Tamil means "sacred big wave", using which this universe was created by Lord Shiva about 132 trillion years ago. Chidambaram in Tamil Nadu, the Sri Natarajar temple's annual Festival, is celebrated on this date.

It takes place on the full moon night in the Tamil month of Margazhi (December–January) and this is also the longest night in a year. Literary and historical evidence in the form of stone inscriptions state that the festival has been celebrated on this day for more than 1500 years. Lord Shiva is praised in Tamil by many names, one of them is Athiraiyan (ஆதிரையன் ), from Thiruvathirai (Thiru + Athirai).

Tamil hymns of Maanikavasagar's Thiruvasagam (particularly the hymns Thiruvempavai and Thiruppalliezhuchi) are chanted in temples. On the very day of Thiruvathirai the idols of Nataraja (Lord Shiva) and his consort Shivagami (Parvati) are taken out of the temple premises for a grand procession. It is one of the major events in almost all the Shiva temples in Tamil Nadu.

Sambandar sung in Tevaram during 7th-9th century, how Thiruvathirai celebrated at Kabaleeshwaram (present day Mylapore, Chennai).

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