I have been unable to find much more about this than what I can gather from the Farmer's Almanac. I suggest looking in the library under American folklore or something similar. Most encyclopedias and dictionaries I have looked at do not even have an entry for Blue Moon, and the technical literature is massively unhelpful! There was, however, an article in Sky and Telescope magazine in the May, 1999 issue by Philip Hiscock that was extremely well written and dispels many misunderstandings about this term.
Copyright 1997 Dr. Sten Odenwald
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