Once in a …

Did you see it?

When we have 2 full moons within a single month, the second full moon is often called a “blue moon.” Hence the phrase, “once in a blue moon.”

Except that’s not right, exactly.

The actual origin of “once in a blue moon” is cited by the Maine Farmer’s Almanac in the early 1900s as the just-about-as-rare time that a season has 4 full moons. When that happens, the 3rd of the 4 full moons was called a blue moon. Following the way our calendar works as set out by the Gregorian calendar reform (as we have since 1582), this kind of blue moon only happens in February, May, August and November.

However, the magazine “Sky & Telescope” helped to change that definition when it defined a blue moon as the second in a calendar month … that, in a twist only history can give us, used data received from the editor of the Maine Farmer’s Almanac that used the other definition!

So, whether you subscribe to the ideas of the Maine Farmer’s Almanac, or the more popularly accepted but historically poorly edited Sky & Telescope magazine, here’s a picture of last night’s moon.

Some will say it’s a blue moon. Some will say it’s yellow, at least in this picture.