Where does the phrase "blue moon" come from?

>I would like to know the origin of the name "blue moon?" I know what a blue
>moon is. Thank you for your time
>

Hello Sarah,

The name "blue moon" is thought to come from the fact that, on very rare
instances, the moon can appear to have a bluish color. This is most
often seen after major volcanic eruptions, such as Mt. Pinatubo, Mt. St.
Helens, etc. However, it is uncertain that this explanation covers the
true reason for the name "blue moon".

Thanks for your question.

Sincerely,
Kurtis Williams

Back to the Ask An Astronomer page.