Blue Moon 12-31-09 (3)
I confess. I adjusted the color temp on this shot to make the Moon appear blue. NASA has in interesting article about the history of "Blue Moon." I encourage you to read the story but here are some snippets for the lazy:
Don't expect the Moon to actually turn blue, though. "The 'Blue Moon' is a creature of folklore," he explains. "It's the second full Moon in a calendar month."I hope you enjoyed learning things from my blog in 2009. Make 2010 a great year!
Most months have only one full Moon. The 29.5-day cadence of the lunar cycle matches up almost perfectly with the 28- to 31-day length of calendar months. Indeed, the word "month" comes from "Moon." Occasionally, however, the one-to-one correspondence breaks down when two full Moons squeeze into a single month. Dec. 2009 is such a month. The first full Moon appeared on Dec. 2nd; the second, a "Blue Moon," will come on Dec. 31st.
The modern astronomical Blue Moon occurs in some month every 2.5 years, on average. A Blue Moon falling precisely on Dec. 31st, however, is much more unusual. The last time it happened was in 1990, and the next time won't be until 2028.