The California sky will be illuminated by a 'Luminous' supermoon and 2 meteor showers. Here's when

California residents are in for a celestial treat this December as a strikingly bright full moon coincides with two notable meteor showers. The last full moon of 2025 will be a supermoon, appearing larger and more luminous than usual. This marks the third consecutive supermoon visible from California, creating a rare opportunity for stargazers.

When to See the December Supermoon in California

The final full moon of 2025 will reach its brightest point at 3:14 p.m. on Thursday, December 4. The moon appears larger because this full moon occurs at perigee, the point in its orbit closest to Earth. At this time, the moon can seem up to 14% bigger and 30% brighter than when it is at its farthest point, known as apogee.

This cold winter supermoon is the third of three supermoons scheduled for 2025. Along Californias coast, it may slightly influence tides, known as king tides, although the effect is minor. According to the Supermoon Visibility Index, California ranks sixth nationwide for supermoon observation, taking into account factors like sky clarity, humidity, elevation, and darkness.

The December full moon is traditionally called the cold moon, reflecting the seasonal drop in temperatures. Other historical names in the United States include the long night moon, snow moon, frost moon, and hoar frost moon. In Europe, it was referred to as the moon before Yule, connecting it to winter solstice celebrations and the return of longer days.

Geminid Meteor Shower Peaks December 1314

One of the years most dependable meteor showers, the Geminids, will reach its peak between the night of Saturday, December 13, and the early hours of Sunday, December 14. Under ideal dark skies, observers can see 60120 meteors per hour. These bright, fast meteors originate from asteroid 3200 Phaethon and often have a yellow hue.

The Geminid display starts around 910 p.m. and continues until dawn. Optimal viewing requires leaving city lights behind and lying flat while looking south. This year is particularly favorable, as skies will stay dark until the waning crescent moon rises around 2 a.m. Watch for yellow-tinted streaks and especially bright fireballs that can appear anywhere in the sky.

Winter Solstice and Ursid Meteor Shower

The shortest day of 2025 occurs on Sunday, December 21, marking the winter solstice and the start of winter. During the solstice, the suns path is at its lowest point, producing the longest shadow of the year. Standing outside at noon allows observers to notice this seasonal phenomenon.

The second meteor shower, the Ursids, peaks overnight from Sunday, December 21, into Monday, December 22. Although less active than the Geminids, up to 10 meteors per hour may be visible under dark skies and a dim crescent moon. Most activity occurs just before dawn, though meteors can appear at any time of the night.

December's Celestial Events: A Rare Astronomical Convergence

This December, California residents are in for an extraordinary celestial experience, with the final supermoon of 2025 coinciding with two significant meteor showers. Notably, this supermoon is the third in a series of supermoons this year, offering an exceptional opportunity for skywatchers to witness the moon at its most luminous. Additionally, the Geminid meteor shower, one of the most reliable annual displays, will peak around mid-December, followed closely by the Ursid meteor shower near the winter solstice. These events make December a highly anticipated month for astronomy enthusiasts.

With the supermoon reaching its peak brightness on December 4, it will appear 14% larger and 30% brighter than usual, as it aligns with the perigee of its orbit. While the moon's influence on tides will be minor, it is still a noteworthy phenomenon for coastal residents. The Geminid meteor shower, which peaks on December 13–14, offers another highlight, with up to 120 meteors visible per hour under ideal conditions. For those planning to observe, escaping light pollution and finding a dark viewing spot will provide the best experience.

Finally, the winter solstice on December 21 marks the start of the season, and with it comes the Ursid meteor shower. While the Ursids are less active than the Geminids, they still offer a fascinating spectacle, with up to 10 meteors visible per hour. This perfect combination of celestial events provides a rare opportunity to witness a variety of astronomical phenomena in the final month of the year.

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• ‘Luminous’ supermoon, 2 meteor showers to light up California sky. Here’s when

Author: Maya Henderson
Maya Henderson is a journalist focused on technology and startups. She has experience in leading IT publications and excels at conducting interviews and creating visual content.