The December 2025 full moon — known as the cold moon — is a supermoon peaking on Dec. 4 at 6:14 p.m. ET, appearing larger because it will be near lunar perigee (Almanac: ~221,965 miles; NASA references ~226,000 miles). The moonrise coincides with the start of the Geminid meteor shower (active Dec. 4–17, peak Dec. 13–14), which can produce up to about 120 meteors/hour under dark skies. The winter solstice follows on Dec. 21, 2025, making early December a great time for Northern Hemisphere skywatchers.
December 2025 Cold Supermoon and Geminids: When to Watch the Night Sky
The December 2025 full moon — known as the cold moon — is a supermoon peaking on Dec. 4 at 6:14 p.m. ET, appearing larger because it will be near lunar perigee (Almanac: ~221,965 miles; NASA references ~226,000 miles). The moonrise coincides with the start of the Geminid meteor shower (active Dec. 4–17, peak Dec. 13–14), which can produce up to about 120 meteors/hour under dark skies. The winter solstice follows on Dec. 21, 2025, making early December a great time for Northern Hemisphere skywatchers.
05:17 AM, 11/20/2025Science
The next full moon of 2025 will be the December "cold moon," a supermoon expected to rise during the longest nights of the year and remain bright and prominent for several evenings. This event will coincide with the start of the Geminid meteor shower and comes just ahead of the December winter solstice.
When and how bright
The full cold supermoon reaches peak illumination on Thursday, Dec. 4, 2025, at 6:14 p.m. ET. The Old Farmer's Almanac lists the moon's nearest point for this event at about 221,965 miles from Earth; NASA often cites similar perigee distances near 226,000 miles when describing supermoons. Because the moon will be low on the horizon and near lunar perigee, it may appear larger and somewhat brighter than a typical full moon.
What is a supermoon?
A supermoon occurs when a full moon coincides with lunar perigee, the point in the moon's orbit closest to Earth. Supermoons often come in short runs; this cycle began in September 2025 and continues through January 2026. The next similar series of notable full moons does not return until late 2026.
Moon phases (selected dates)
- New moon: Nov. 20, 2025
- First quarter: Nov. 28, 2025
- Full moon (Cold Supermoon): Dec. 4, 2025
- Last quarter: Dec. 11, 2025
- New moon: Dec. 19, 2025
- First quarter: Dec. 27, 2025
The Geminid meteor shower
The Geminids, often regarded as the year's most active meteor shower, are active from about Dec. 4 through Dec. 17, with the peak on the night of Dec. 13–14. Under ideal, dark-sky conditions, observers in the Northern Hemisphere may see up to 120 bright Geminid meteors per hour at peak. Unlike most showers that originate from comets, the Geminids come from asteroid 3200 Phaethon, which sheds debris that intersects Earth's orbit each mid-December.
For best viewing, go to the darkest practical location and give your eyes about 30 minutes to adapt. Meteor activity often increases around midnight and can be especially active near 2 a.m. local time, though Geminids can be visible from around 9 p.m. onward.
Winter solstice and what follows
The Northern Hemisphere's winter solstice falls on Sunday, Dec. 21, 2025, producing the shortest day of the year — roughly 9 hours, 17 minutes of daylight for many locations. The first full moon of 2026 is expected to be the January wolf supermoon, rising on Saturday, Jan. 3, 2026.
To find exact moonrise and moonset times for your location, consult a local almanac or astronomy service and enter your ZIP code or coordinates.
By Maria Francis