Friday, Aug. 31, 2012 is a “blue moon”—the second full moon within a calendar month.
There was a full moon on Aug. 1st, so tonight's full moon is a blue moon.
The blue moon looks the same as any other full moon. Why it is called a “blue moon” seems to be lost in antiquity.
Blue moons are not as rare as most people realize. They occur about once
every 2 ½ years.
The last blue moon was Dec. 31, 2009, and the next one will be July 31, 2015.
So be careful when you say that you will do something, such as take the kids to Disneyland, “once in a blue moon.” It might come sooner than you think!