Once Indra lost his kingdom and found that only if he consumed the Divine Nectar he could rule. So there was a tug of war between the devas and asuras to obtain this nectar. The Devas and Asuras got together to churn the ocean, using Mandramalai & Vaasuki, the snake. As they continued to churn the ocean, Vaasuki the snake began to tire and started spewing its poison. Siva came and consumed all the poison. Thus Siva became blue up to his throat and is also known by the name "Neelakandan" ( neela-blue colour, kandam-throat).
Goddess Parvati rushed and held his neck so that the poison would not spread to the whole of his body. Shiva then became drowsy and selected a village called Surutapalli (near Chennai), where he is seen sleeping on the lap of Parvathi. This is the only temple that houses Lord Shiva in a sleeping position. Narada, meanwhile, passed on the message and down came the Devas, Brahma, Vishnu and the Saptarishis, to have darshan. They were promptly stopped by Nandi who asked them all to come after some time, as Shiva was resting. All of them waited. Shiva, when he woke up, was filled with extreme happiness and danced ("Ananda Thandavam"). This day, when the Devas, Brahma, Vishnu, Narada and Saptarishis had Shiva darshan was a Krishnapaksha Trayodasi (Stiravaram, Saturday). This is the Mahapradosham day. Pradhosham, generally, is a significant occasion observed with great piety at all Shiva temples. It is believed that all the Devas & Gods are assembled in the Shiva temples during Pradosham time. Further, the first pradosham was on a Saturday & hence "Sani Pradosham" is even more auspicious.
Shiva
If you wish the Archana to be performed in God's name, do not fill in the name and Nakshatram.