If you thought one supermoon was bright, how about three….? The full Moons of summer 2014—July 12th, August 10th, and Sept. 9th–will all be supermoons.
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.
This coincidence happens three times in 2014. On July 12th and Sept 9th the Moon becomes full on the same day as perigee. On August 10th it becomes full during the same hour as perigee—arguably making it an extra-super Moon.”