Closed Kaunting Kaalaman

MANILA - Tonight, a blue moon rises. But how rare does this happen?

A definition of this phenomenon from the Maine Farmers Almanac says farmers call the third full moon of a season with 4 full moons a blue moon.

Another definition, meanwhile, by astronomer J. Hugh Pruett -- one that is more popular -- says a blue moon is the second full moon within a month.

Regardless of which one's right, one thing is for sure: the moon will not turn blue during the blue moon phenomenon.

"Most blue moons look pale gray and white, indistinguishable from any other moons you've ever seen," says National Aeronautics and Space Administration (NASA).

But the moon could turn blue if a big fire or strong volcanic eruption happens because of the smoke or ash that practically filters light from the moon. -- with report from Kuya Kim Atienza, TV Patrol