What is a blue moon?
A blue moon is the second blue moon that occurs within one month. Each month typically has one full moon, for a a total of 12 full moons in one year. There are times however that there may be 13 or more full moons in one year. If this occurs one (or more) of the months would have had two full moons within the same month. This “second” full moon in one month is called the Blue Moon.
Each full moon occurs just about every 29 days in one calendar month, sometimes it is possible that in the longer months an “extra” full moon shows itself, making it the “Blue Moon.” How rare are blue moons? The estimate is that every 2.5 to 3 years we will have a blue moon. Think of it this way, every twenty years we will have about 6-8 blue moons. Do you think that is rare?
So, will the blue moon really be blue in color? Most experts agree that the myth of the moon actually being blue in color was the result of gases, smoke, or some type of haze covering the view of the moon only making it appear blue in color. Ever since then the name “blue moon” has been used to describe the rare appearance of the second moon in one month.