10 FAQs about the Blue Moon (The Astronomy Cafe)

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I know that these articles will dismiss the naming of the 'second full moon of the month' as a big misunderstanding, but as an astronomer, I will continue to define a 'Blue Moon' that way because otherwise this second full moon of a month will go unnamed, unlike the second new moon which is called the Black Moon, the Finders Moon etc.!! (Dr. Sten Odenwald, May 2000)

Beginner

  1. Who invented the term 'Blue Moon'?
  2. What is the atmospheric process that causes a 'Blue Moon'?
  3. Exactly when did the term 'Blue Moon' first get used?
  4. What facts or lore have to do with the Blue Moon?
  5. Does a Blue Moon happen at the same time everywhere on the Earth?
  6. What is a Blue Moon and when have the most recent ones occurred?
  7. When will the next Blue Moon happen?
  8. Can there ever be two Blue Moons in a single year?
  9. Can you have two Blue Moons in a year?
  10. When was the last Blue Moon in February, and when will the next one be?

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