All days in the month of Kartik are considered auspicious, with Nagula Chavithi being one of the most important festivals. This year, it falls today, October 25th, Chavithi begins at 1:19 am and ends tomorrow at 3:48 am. Experts say the best time to worship the Naga deities is 8:59-10:25 am, during the Rahu period.