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Astronomy News: How Often Does a Blue Moon Occur?
A blue moon will occur this week on August 31, 2012. What is a blue moon, do you ask? Well, break out your astronomy books and let's take a look at this rare phenomenon and learn more about earth's nearest "friend", the moon!
Will the Moon Really be the Color Blue?
No, the moon will not actually be the color blue. There are actually two existing definitions of a Blue Moon:
An article “Once in a Blue Moon” by James Pruett published in the March 1946 Sky & Telescope magazine declared that the second full moon in a calendar month is called a Blue Moon. Since the period between two full moons is about 29 ½ days, this occurs somewhat rarely. This definition originated from a simplified definition of a Blue Moon from the Maine Farmer’s Almanac.
The actual definition of a Blue Moon in the 1937 Maine Farmer’s Almanac is actually quite different. A Blue Moon was defined as the third full moon of four in a season. Since one season (fall, winter, spring, and summer) typically has only 3 full moons, this is again a rare occurrence.
Since then, the term “once in a blue moon” has come to refer to something that occurs rarely or is almost impossible.
How did the term Blue Moon originate?
One theory for the origination of the term was from old English term “belewe” which means “to betray”.
How often do Blue Moons occur?
On average, a Blue Moon happens every 33 months (or every 2-3 years). February will never have a Blue Moon; months that have 31 days have a much better chance.
Can you have more than one Blue Moon in a year?
Yes, the last time this occurred was in 1999 and next one will be in 2018.
Can the moon ever look blue?
Actually this has occurred in the past primarily due to dust or smoke in the atmosphere. This can alter the appearance of the moon to take on a bluish tint.
The next Blue Moon will be on July 31, 2015.
For more astronomy information, Astronomynewstoday.blogspot.com is another great resource for up to date astronomy news daily.