Tonight Look For A Rare Blue Moon

Tonight, Look For A Rare (But Not Quite Blue) Moon
People are silhouetted against a nearly full moon as they ride an attraction at Worlds of Fun amusement park Thursday in Kansas City, Mo. July 31 marks the second full moon of the month, a rare occurrence that has come to be known as a "blue moon."
But don't expect to see a new hue. A blue moon, at least according to the modern definition of the term, has nothing to do with color. It simply means a second full moon in the same calendar month.

As NASA explains in the video above: "Most blue moons appear pale gray and white, just like the moon you've seen on any other night."

And that doesn't happen very often (the last time was in August 2012, and the next time will be January 2018), so "once in a blue moon" is a phrase still worthy of a rare occurrence.