A tip from WFMY-TV meteorologist led us to the NASA site that explains, "This May’s full Moon is a 'super Moon,' as much as 14% bigger and 30% brighter than other full Moons of 2012." When can we see this super, or perigee, moon? This go-around, the perigee moon happens just before midnight on Saturday, May 5. "Full Moons that occur on the perigee side of the Moon's orbit seem extra big and bright."

The full Moon has a reputation for trouble. It raises high tides, it makes dogs howl, it wakes you up in the middle of the night with beams of moonlight stealing through drapes. If a moonbeam wakes you up on the night of May 5th, 2012, you might want to get out of bed and take a look. This May’s full Moon is a "super Moon,” as much as 14% bigger and 30% brighter than other full Moons of 2012.
The scientific term for the phenomenon is "perigee moon." Full Moons vary in size because of the oval shape of the Moon's orbit. The Moon follows an elliptical path around Earth with one side ("perigee") about 50,000 km closer than the other ("apogee"). Full Moons that occur on the perigee side of the Moon's orbit seem extra big and bright.
Such is the case on May 5th at 11:34 pm Eastern Daylight Time1 when the Moon reaches perigee. Only one minute later, the Moon will line up with Earth and the sun to become brilliantly full. The timing is almost perfect.