If you saw the Blue Moon yesterday then make the most of it. You will not see another until July 2015.
If you cannot remember when the last one was then let us remind you it was New Year’s Eve 2009.
Of course it is not really blue! The name reflects the relative rarity of two full moons in a month and is linked to the saying “once in a blue moon.”
There is nothing scientific about it, and it has no astronomical significance.
Occasionally it is possible to see quite literally a blue moon but that occurs mostly when ash from forest fires or volcanic eruptions pollutes the atmosphere and it can make the moon appear to be tinted blue.