BUFFALO, NY - Skywatchers are being treated to a rare site this week.

The phenomenon is called a supermoon, and it happens when a full moon coincides with the moon's closest transit to Earth. This year, however, it's even more spectacular. According to NASA, this supermoon is the closest full moon to earth since 1948. A full moon this close to Earth won't happen again until 2034.

With the moon this close to Earth, the full moon appears up to 7% bigger and 15% brighter than usual.

If you missed the supermoon Sunday night or Monday morning, you'll have another chance to see it when the moon rises on Monday night.