Sankashti Chaturthi Vrata is an auspicious day dedicated to Ganesha and it falls on the fourth day after Poornima or full moon day in a traditional Hindu calendar. The date of Sankashti Chaturthi Vrat is December 21, 2013. Moonrise time or Chandrodaya is at 9:24 PM in Mumbai. Chaturthi the fourth day during the lunar fortnight is dedicated to Ganesh. Sankashti Chaturthi Vrata falls during the waning phase of the moon. Fasting, from sunrise to sunset or till sighting of moon, is undertaken by Ganesh devotees.
It is popularly believed by Ganesh devotees that observing Sankashti Chaturthi Vrata will bring material progress, happiness and fulfillment of desires.
The importance of Sankashti Chaturthi Vrat was narrated by Sri Krishna to Yudhishtira. Significance of it is also found in the Narasimha Purana and Bhavishaya Purana.