Date: Ganesh Chaturthi is celebrated as the birth anniversary of Ganesha (Vinayaka), the God of Wisdom and Prosperity on the fourth day of Bhadra in August - September.
Legend: "How did Vinayaka acquire siddhis (supreme powers)? His parents held a contest for their two sons - Ganesha and Subramanya. They said they will offer their grace in the form of a fruit to whoever came first in circumambulating the universe. The younger son, Subramanya, set out immediately on his peacock to go round the universe. On seeing Subramanya approaching his parents, almost at the end of his trip, Vinayaka, who had been quietly sitting all the while, got up and went round the parents and sat down. Parvathi (symbol of Creation) observed that Subramanya, who had taken so much trouble to go round the universe, should be declared the winner. Parameswara (Shiva) asked Vigneswara (Ganesha) what was the inner significance of his going round the parents. Ganesha replied: "The entire universe is permeated by both of you. The entire creation is a manifestation of the Shiva-Shakti form. It is an act of delusion to attempt to go round this phenomenal universe. To go round both of you is the true circumambulating of the cosmos."
Then Parvathi exclaimed: "Yours is the fruit." Ganesha became the Lord of the Divine hosts (ganas). Easwara (Shiva) was so much impressed with the supreme intelligence of Vinayaka that he told him: "All those who wish to worship Me, will offer their worship first to you." Such was the grace showered on Vinayaka. What is the reason? Ganesha's faith in the Lord and His omnipresence. The right path for all people is to develop faith in God and lead godly lives."
There is astronomical support also for the Ganesha festival, celebrated on the fourth day of the bright half of Bhadrapada lunar month. A constellation with the appearance of the elephant head becomes brightly visible on this very night in the sky.
Legend from: Sanathana Sarathi