"Your last chance to see a blue moon until 2015 will come around this Friday (Aug. 31), but don't expect an azure hue in the sky.
In fact, "blue moon" refers not to color, but to rarity. Blue moons are defined as either the fourth full moon in a season, or, more recently, as the second full moon in a month. It's the second definition that covers August's blue moon; the month's first full moon was on Aug. 1."
Credits: Stephanie Pappas, LiveScience Senior Writer
Published: 08/29/2012 08:31 AM EDT on LiveScience