CLUE: It has nothing to do with it being the colour blue, although the Moon can develop a bluish tone caused by excessive dust particles in the atmosphere (such as when Mount St Helens erupted in 1980).
Well, the modern-day definition of Blue Moon refers to the second full Moon in a calendar month with two full moons.
The last Blue Moon was on 31st August 2012 but you’ll only have to wait another couple of days until the next one, this Friday (31st July 2015). Make the most of it though, as the one after won’t come along until 31st January 2018!
In the meantime, I’ll leave you with Frank Sinatra singing “Blue Moon”, of course!
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