Once In A Blue Moon

Tonight's moon is blue.  No, not in color,  Tonight's beer is also blue but not in color either.  But that's a different story.
Blue moons (the kind in the sky) don't come around very often.  The more common kind of blue moon is when there is a second full moon in a single calendar month.  Most months just have one full moon.  The last blue moon of this kind was on August 31, 2012.  The next one will be in July, 2015.  So don't hold your breath for those.
Don't hold your breath for the next blue moon we had tonight either.  Tonight's blue moon was a seasonal blue moon.  Huh, you say.
Most of the time there are only three full moons in a single season but every once in awhile there are four.  Tonight's was the fourth full moon in this season -- summer.

It's not too late.

Step outside and see the blue moon.  And then you can come back inside and finish your blue moon beer.