A supermoon is popularly defined as a new or full moon that coincides with the lunar orb making an especially close approach to Earth. This supermoon was just 221,824 miles away.
How to See the Brightest Supermoon of 2017
Our cosmic companion is about to put on its best show of the year—here’s how to watch.
Tonight, sky-watchers around the world will get a chance to revel under the first—and last—full supermoon of the year. Sometimes called the cold moon in the Northern Hemisphere, the December 3 full moon will be relatively close to Earth and will appear about seven percent larger and 16 percent brighter than usual.
The moon’s orbit around Earth is not a perfect circle but is somewhat elongated. That means the moon changes its distance to Earth by a few thousand miles over time, reaching a closest point (perigee) and a farthest point (apogee) in any given month. A supermoon is the popular term for a full or new moon that coincides with the lunar orb making an especially close