Blue Moon….

A Blue Moon, Super Moon and Blood Moon are all being present tonight for the first time since 1866.

Once in a blue moon…an expression that we have generally all come across at some point. Does, “I only go out for dinner or the cinema once in a blue moon now that I have children“, sound familiar?? Well, have you ever wondered where the expression comes from…..



The definition that we commonly go with in my generation is that an actual blue moon is the second full moon in a month. This was coined after a bit of a mix up back in 1946, when an article entitled “Once in a Blue Moon” appeared in Sky & Telescope written James Hugh Pruett (1886-1955), who was an amateur astronomer living in Eugene, Oregon USA. He had attributed it to the second full moon in a month. Originally it had been associated to the more complicated formular of the fourth full moon of a farming season. Some saw his version of the second full moon as a mistake but it has stuck as the more common version.

The name blue moon has been subject now of songs, poems and also used in every day language. When it’s used it stands for ‘never’ or ‘rarely’. I take all new parents back to the quote in the first paragraph!

Is the moon actually blue?…No. When there has been recorded sightings of the moon having a blue tinge it’s been when there has been volcanic ash which has risen and caused this slight effect.

It seems to transcend the years and still maintains a modernity that is as rare as a, dare I say it…….a blue moon!

There are many other names for full moons, which ones do you know?

Or, do you have your own tales of when you’ve used the term ‘once in a blue moon’?

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