>I kept hearing about the Blue Moon. I’d heard about it before, but never really knew what made it a “Blue Moon”.

Thus the searching began:

According to modern convention, a “blue moon” is the second full moon in a calendar month. However, researchers for Sky and Telescope Magazine have recently determined that the Maine Farmers’ Almanac originally established a different definition of the term in 1937. According to the Maine almanac, a blue moon occurs when a given season has four full moons instead of the usual three. In this case, the third full moon of the season is considered the “blue” moon. Whichever interpretation of the term is used, the reason it is called a “blue moon” is odd logic: a) the Moon appears blue in color very rarely, b) two full moons in one month (or four in one season) is also a rare phenomenon, so, c) when a second full moon occurs in a single month (or when four occur in a single season), we have what is known as a “blue moon.”