
At the end of 2009, a blue moon will preside over the annual New Year’s Eve countdown and accompanying ball drop in Times Square.
But what does this mean?
For most people, it will just mean a full pie in the sky Thursday night. A blue moon is simply the second full moon in month. It doesn’t actually have anything to do with color at all.
Usually, there’s only one full moon each month because the monthly calendar was built on the lunar cycle 29.5 days). But once every 2-1/2 years, those extra half days add up to two full moons in a month.
So where does the name come from?
According to NASA's website, the term blue moon was "used in much the same way we use the term 'harvest moon.'...