A full moon happens once every 30 days or so. But the supermoon is much rarer.

The moon will be the biggest and brightest over the weekend. It hasn't been this bright since November 2016. Sunday, December 3rd, the moon will be 7% bigger and 16% brighter than the rest of the year. This distance to the moon fluctuates during orbit. When the moon is closest to the Earth, its about 225,000 miles away and 16,500 miles closer than usual.

The Supermoon of 2016 was the biggest and brightest we had seen since 1948. It won't be that bright again until 2034. But Sunday's Supermoon will still be a sight for anyone looking to the sky.

Maybe George Bailey knew that night there was going to be a Supermoon that night outside with Mary Hatch.