You've heard the old expression, "once in a blue moon," but most folks don't know exactly what that means other than something that doesn't happen often.  Tonight, we will be treated to a rare blue moon.

"Blue Moons" are not blue in color, so you won't see anything other than a bright, full moon in the nighttime sky.

There are a couple of definitions for a "Blue Moon" and neither is scientific.

One holds that anytime you have two full moons in the same calendar month, the second is considered a "Blue Moon."

The other is when there are four full moons in a single season, Summer, Winter, Autumn or Spring.  When that happens, the third full moon of the season is considered a "Blue Moon."

The next blue moon is in 2015.  In 2018 there will be TWO blue moons.  That only happens once in a ....

If you want more information on matters celestial, visit:  http://www.sloanlongway.org/LongwayPlanetarium.aspx