Fri, Jul 31, 2015, 04:20 PM
Blue moon is a rare sight. If two full moons occur in a month, the second one is called 'blue moon.' This will appear in the night sky today. A full moon had occurred on the first of July. Normally, one full moon occurs every 29 days, that is one in a month. 12 full moons occur every year. But once in three years, 13 full moons are seen in a year.