How to watch the last supermoon of the year
NEW YORK (AP) — The last supermoon of the year will soon shine in the December sky.
The Moon’s orbit around Earth is not a perfect circle, so it gets closer and closer as it moves. When a full moon is closer to Earth in its orbit, what is called a supermoon occurs. This makes the moon appear up to 14% larger and 30% brighter than the faintest moon of the year, according to NASA.
Supermoons occur several times a year in clusters, taking advantage of the sweet spot of the moon’s elliptical orbit, and Thursday night’s event is the last of three consecutive events in 2025.
The supermoon can be seen in a clear night sky without any special equipment. But it can be difficult to discern this subtle change with the naked eye.
Whether it’s a supermoon or not, the moon also appears larger when it’s close to the horizon because of something called the lunar illusion. It’s a strange visual trick that experts can’t yet explain.
“When you have a supermoon, this effect is slightly more striking,” said astronomer William Alston of the University of Hertfordshire.
Tides might be slightly higher during a supermoon because the moon is closer to Earth, but again the difference is not very noticeable.
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