On Monday, November 14, the Moon will be full, and also near its closest approach to Earth. It’s a “supermoon,” appearing slightly bigger than a normal full Moon.
Supermoons are not unusual. There are often several per year, and a large crowd of visitors enjoyed a lunar eclipse supermoon last year here at the Phoebe Waterman Haas Public Observatory. But the November full Moon is actually the closest to Earth in 68 years, and the closest for another 18 years, making it a “super duper Moon!”
The closest supermoons are about 14% closer to us than the most distant “micromoons,” a difference of about 50,000 kilometers (30,000 miles), and shine about 30% brighter. This difference is difficult to notice, but you can measure it by holding small objects like pencils at arms’ length to see which object is the right size to barely cover the Moon. Repeat the experiment with other full Moons and compare. Try cutting slots in a card to get a more precise measurement.
The exact moment when the Moon will be closest to you depends on your location on Earth, the angle of the Moon in the sky, and even your altitude. For most U.S. observers, the closest moment will occur sometime between midnight and dawn on Monday. However, the Moon will be almost as close on Sunday evening or Monday evening if you don’t catch it early on Monday.
I hope you will join me in getting up early this Monday morning to watch a large, bright moonset!
Update - November 14, 2016:
Monday, November 14 was a crystal clear morning in Washington, DC for observing the supermoon. The Moon did look extra-brilliant! There's still an opportunity to catch this supermoon. It will appear almost as large on Monday evening shortly after sunset. While Washington, DC may be too clouded to see it clearly, the rest of the world can enjoy the supermoon. Just put your back to the last light of sunset and look for the Moon peeking over the horizon. And if you do miss it, remember that the supermoon looks pretty much like any other full Moon: that is to say, beautiful!