
It will appear to be 14 to 30 percent larger than normal, due to a phenomenon called the lunar perigee.
When the full moon lines up within 12 hours of the lunar perigee, it appears larger.
"The lunar perigee is the point in the lunar orbit that brings the moon closest to Earth. The moon's orbit is slightly elliptical; at its closest approach, the moon is 225,622 miles from Earth. At it's farthest, the moon is 252,088 miles away."
In other words, the moon will be a little bit closer to us on Sunday, and it will look a lot bigger.
The moon will again look this large in August 2013, and will also seem bigger in July.
But other than looking large, the supermoon doesn't really have any other affects on the Earth. There were reports that supermoons were responsible for disasters like the tsunami in Japan and the sinking of the Titanic, but there is not proof.
John Bellini, a geophysicist, said, "A lot of studies have been done on this kind of thing by USGS scientists and others. They haven't found anything significant at all."
Sources: Inquisitr, Huffington Post Reported by Opposing Views 7 hours ago.