You might want to see a previous answer to this question which I wrote. Originally when I answered this question back in 1996 I said that I didn't know. "The Oxford English Dictionary has no listing under 'Blue Moon' or 'Moon - Blue'. This seems a bit odd since I believe the term has been in popular usage for at least 100 years! ". Based on the great piece of historical research done by Sky and Telescope magazine in their 1999 article, I now realize in 2000 that I had been laboring under the same popular misconception as many others about the way this name came about. I still accept the 'second full moon of the month' definition though. What else could you possibly call such a rare and beautiful full moon?
Copyright 1997 Dr. Sten Odenwald
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