Blue Moon


| 1/11/2010 4:50:17 PM


Tags: moon phases, blue moon, New Year's Eve,
Sam Moore  
Sam Moore   

“Blue moon, you saw me standing alone, without a dream in my heart, without a love of my own.”

— “Blue Moon,” Richard Rodgers and Lorenz Hart, 1934

I’m writing this on New Year’s Eve and, although it’s overcast outside and I can’t see it, there’s what is commonly called a “blue moon” overhead.

When I was a kid, folks often used the expression “once in a blue moon” or “never in a blue moon” to describe something that occurred very rarely, or that might never happen at all. I didn’t know what the term referred to since I’d never actually seen a blue moon; every moon looked yellow or white or maybe gray to me.

There have been several occasions when the moon actually did look as though it was blue, mainly due to dust, smoke or ashes from some cataclysmic event on earth permeating the atmosphere. One such event occurred in 1883, when the Indonesian volcano Krakatoa erupted, spewing so much ash into the atmosphere that moonbeams passing through the clouds of ash appeared blue or green for several years after.

A full moon occurs every 29 days, so it’s possible for there to be two in a single month, although it is relatively rare, happening on an average of once every 2.7 years. In 2009 there was a full moon on Dec. 2 and another on the 31st.