In 2010, New Year’s Eve was just a little bit more special than usual, as it was graced by a blue moon. Now, don’t just jump to the conclusion that this means the moon itself was blue, as this was not the case. It was, in fact, the second full moon in the same month, an occurrence known as a blue moon. The expression “once in a blue moon” is often used to describe rare events, although blue moons aren’t all that rare. A blue moon occurring on New Year’s Eve, however, is incredibly rare and hadn’t happened since 1990. Know more.