The Blue Moon of July 31 marks the second full moon of the month. For our latest on the lunar event, read: Blue Moon Full Moon Rises Tonight: What to Expect
On Friday, much of the world will have the opportunity to observe a Blue Moon: A somewhat rare occurrence that doesn't have anything to do with the moon's color.
During most years, the Earth experiences 12 full moons, one in each month. But some years, such as 2015, have 13 full moons, and one of those "extra" lunar displays gets the label of Blue Moon.