Once in a Blue Moon

Blue Moon over the Axarquia, Spain We all know that the phrase “once in a blue moon” means “rarely”, but do you know what a Blue Moon really is?

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!

Whilst you’re here, you might also enjoy:

Searching the Night Sky for the International Space Station

Malaga’s Sensational Phoenician Moon Goddess