New Year’s Eve is fast approaching. Time to say goodbye to 2009 and toast in a new year and a new decade. While you celebrate this special evening, be sure to take a look at the night sky — not for fireworks but for the full blue moon!
It won’t look blue, but thanks to popular tradition (and a mistake), a second full moon in a month is referred to as a “blue” moon. While it sounds rare, it’s not really that unusual. On average a second full moon in a month (a.k.a. blue moon) occurs, on average, about every 32 months.
Why “Blue” Moon?
For the longest time nobody knew exactly why the second full Moon of a calendar month was designated as blue moon. One explanation connects it with the word “belewe” from the Old English, meaning, “to betray.” Perhaps, then, the Moon was “belewe” because it betrayed the usual perception of one full Moon per month.
However, in the March 1999 issue of Sky & Telescope magazine, author Phillip Hiscock revealed one somewhat confusing origin of this term. It seems that the modern custom of naming the second full Moon of a month “blue,” came from an article published in the March 1946 Sky & Telescope magazine. The article was “Once in a Blue Moon,” written by James Hugh Pruett. In this article, Pruett interpreted what he read in a publication known as the Maine Farmers’ Almanac (no relation to this Farmers’ Almanac, published in Lewiston, Maine), and declared that a second full Moon in a calendar month is a “Blue Moon.”
Interestingly, it was during the period from 1932 to 1957 that the Maine Farmers’ Almanac first suggested that if one of the four seasons contained four full Moons instead of the usual three, the third should be called a blue Moon. But thanks to a couple of misinterpretations of this arcane rule, first by Sky & Telescope magazine and then many years later by a syndicated radio program, most people accept and refer to the second full Moon in a month as a blue moon.
Toast To the Full Blue Moon
Last time we saw a full blue New Year’s Eve Moon was in 1990, and the next one after 2009 won’t be until 2028. So wear some blue this year, serve some blue food, and be sure to share some full moon/blue moon trivia.
Happy New Year!