The last full Moon of 2025, known as the Cold Moon, will reach its peak on Thursday, December 4, but astronomers say the best time to enjoy the spectacle is actually the night before, on Wednesday, December 3.
This year’s final supermoon brings with it a special highlight: a close encounter with the Pleiades star cluster. The nearly full Moon will move toward and then pass directly in front of the cluster, creating a striking celestial alignment.
In astronomy, such a pairing is often described as a pas de deux, referring to the gravitational interaction between two objects moving together in the sky. December’s full Moon will also be at perigee, its closest point to Earth, making it appear slightly larger and brighter than usual.
The occultation will be visible across multiple regions. In the UK and Europe, the event occurs early Thursday morning before sunrise, though the Moon and Pleiades will be visible rising in the east the previous evening. In eastern North America, the Moon will cross the cluster early Wednesday evening, while in western North America the event may already be underway at nightfall.
After the occultation, the Moon will reach its full phase at 6:14 p.m. ET on Thursday, December 4.
The Cold Moon is the third and final supermoon of 2025. Earlier full Moons this year included the Wolf Moon in January, Snow Moon in February, Worm Moon in March, Pink Moon in April, Strawberry Moon in June, Buck Moon in July, Corn Moon in September, Hunter Moon in October, and Beaver Moon in November.
The December full Moon takes its name from the harsh winter conditions that typically accompany this time of year. Many traditional Moon names originate from Native American cultures, reflecting natural changes and seasonal events.
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