This year's last supermoon event was its best. As night fell around the world, sky gazers were treated to the brightest supermoon of the year.
Photos show a full moon that was brighter, larger, and closer to Earth than 2017's previous full moons. The relatively rare lunar event can only be seen when the moon's orbit and cycle coincide at just the right time.
When a full moon reaches the point in its orbit that brings it closest to Earth, it makes for an imposing sight. This happens only occasionally, because the moon's orbit is shaped more like an ellipsis than a perfect circle.
The December 3 supermoon will appear about seven percent larger and 16 percent brighter than a typical full moon, says National Geographic night sky expert Andrew Fazekas. He notes that the moon will be at its closest at 4 a.m. ET. The best time to see the supermoon at its brightest, however, is just after sunset. This is thanks to an optical effect called the moon illusion.
For sky watchers whose views are obstructed by cloudy skies, the next supermoon will take place shortly after the new year, on January 2.