Astro Bob column: Modern definition of 'blue moon' a case of misinterpretation
Tonight is the blue moon -- which isn't blue, of course, unless you happen to be near a volcano.
It was actually a mistake by an amateur astronomer in Sky & Telescope magazine in 1946 that led to our current definition of "blue moon" as the unusual second full moon in a month.
Are you a newspaper subscriber but you don't have a Digital Access account yet? https://secure.forumcomm.com/?publisher_ID=40&event=subscriber/lookup.
You will need your subscription account number and phone number. Not sure if you have an account? Email us at firstname.lastname@example.org and we can help you.