Tonight: December 2025 Cold Supermoon Rises as the Geminid Meteor Shower Begins

Why the Moon Looks So Big Tonight: The December 2025 full moon — commonly called the "cold moon" or the "long night moon" — will appear unusually large and bright as it rises in the constellation Gemini. It’s the last prominent supermoon of the season and arrives just as the famous Geminid meteor shower gets under way.

How Close Is It? According to the Old Farmer’s Almanac, this full moon will come within about 221,965 miles (approximately 222,000 miles) of Earth. A "supermoon" occurs when a full moon coincides with the Moon’s closest approach (perigee) in its elliptical orbit, making the lunar disk look slightly larger and brighter than usual. The Moon’s low position on the horizon during rise and set also creates the familiar ‘‘moon illusion,’’ which can make it seem even bigger.

When To Watch: The December cold supermoon reaches peak illumination on Thursday, Dec. 4, with maximum light around 6:14 p.m. ET, and it will rise near the same time across several nights (including Dec. 3–5), which helps the Moon appear large for multiple evenings. For exact moonrise and moonset times in your area, consult a local almanac or online tools such as the Old Farmer’s Almanac.

Geminid Meteor Shower

The Geminids are one of the most reliable and productive meteor showers of the year. The display runs roughly Dec. 4–17, with the highest activity expected the night of Dec. 13–14. Under ideal, dark-sky conditions at the peak, observers in the Northern Hemisphere can see up to about 120 meteors per hour.

Unlike most showers that come from comet debris, the Geminids originate from asteroid 3200 Phaethon. The meteors appear to radiate from near the star Castor in the constellation Gemini, but they can streak across much of the sky.

Viewing Tips

• Find the darkest possible site away from city lights and allow ~30 minutes for your eyes to adapt to the dark.
• The best viewing window is typically after midnight into the pre-dawn hours; many Geminid meteors become active as early as 9 p.m., with peak rates around 2 a.m.
• While looking toward Gemini (east) helps identify the radiant, Geminid meteors can appear anywhere in the sky, so a wide field of view is best.
• Use a reclining chair or blanket so you can comfortably watch a large portion of the sky.

Other Dates and Notes

• Full Moon: Dec. 4, 2025 (peak illumination ~6:14 p.m. ET)
• Last Quarter: Dec. 11, 2025
• New Moon: Dec. 19, 2025
• First Quarter: Dec. 27, 2025

The first day of winter — the winter solstice — falls on Sunday, Dec. 21, 2025, bringing the shortest day of the year with about 9 hours and 17 minutes of daylight in many northern locations. The sequence of supermoons that began in September 2025 continues through January 2026; the next full moon (the January 2026 "wolf supermoon") will rise on Saturday, Jan. 3, 2026.

Author: Maria Francis. Originally published on NorthJersey.com.