This is a festival , celebrated on the day of Thiruvadirai star in Margazhi month.It is essentially Shaivite festival and celebrates the Cosmic dance of Lord Shiva.
Arudra star is one of two stars that have the prefix "THIRU". Another star is Onamstar - "Thiruonam"favoured for Shiva andMahavishnu repectively.
|Lord Nataraja - Cosmic Dance|
|Lord Nataraja Procession-Therottam|
In Chidambaram abhishekam for the Lord on thiruvadirai day in Margazhi will be performed in a grand manner and the devotees will be given KALI as prasadham.Obtaining the prasadam , is attainment of bliss through the Lord.
Story behind why Kali is given as Prasadham :
A devotee named Sendanar had the habit of eating food after offerring it to Lord and then distribute among other devotees . Only the leftover he will eat.On the tiruvadirai day , due to constant bad weather he couldn't get any essential items for preparring proper meal.He had no other option but to mix water with rice flour and prepare a mashed paste.Lord Shiva understood his predicament.He wanted the people to know how sincere his devotee was to him.He disguised himself as a siva devotee and enjoyed what was given to him as food.And as he stood for a while in the Nataraja Sanctrum,The Lord Showered the Kali all over the premises , in recognition of his deep devotion.Since the day the miracle happened Kali is the special offering to Lord Nataraja on Margazhi.
|Arudra Darisanam-Chidambaram Temple|
There was another muni and devotee of Lord Shiva in that place, called Viyaagra paadha. He prayed to God to get the legs of tiger, so that he can pluck flowers early in the morning to offer to the God, before any bee touches the flower. He was also praying God to see His Great Dance for a long time.Pleased with their prayer the God appeared on the Thiruvaadirai day and danced in Chithamparam. The Nataraja image of the Lord is prayed with great devotion this day. In Chithamparam and other temples it is celebrated as Arudraa dharshanam. In this festival abhisheeka [holy anointing] of Lord Nataraja takes place early in the morning and then He comes around the town.
In all Lord Shiva Teples Arudra Darshan is celebrated with great devotion. Arudra Darisanam is celebrated with great devotion in the Hall of Gold - Kanakasabhai at Chidambaram; Thillai - The Hall of Silver Velli Sabhai at Madurai; The Hall of Rubies - RatnaSabhai at Tiruvalankadu; The Hall of Copper - TamaraSabhai at Tirunelveli and the Hall of Pictures - ChitraSabhai in Kutralam.