Key Highlights
- The December Ursid meteor shower peaks next week under dark skies, offering a small chance of unexpected activity.
- The Ursids are often overshadowed by the more prolific Geminid meteor shower in December.
- The peak of this meteor display usually occurs during the overnight hours of Dec. 21-22, radiating from the vicinity of the bright orange star Kochab in Ursa Minor.
- No unusually strong activity has been forecasted for 2025, but an enhanced rate might occur on December 22.
The Forgotten Ursid Meteor Shower
When skywatchers think of meteor showers in December, they immediately think of the Geminids, which over the years have evolved into one of the most prolific and reliable annual displays. However, there is another notable meteor shower that occurs during this month: The December Ursids.
The Ursid Meteor Shower
The Ursids are so named because they appear to fan out from the vicinity of the bright orange star Kochab in the constellation of Ursa Minor, the Little Bear. Kochab is the brighter of the two outer stars in the bowl of the Little Dipper (the other being Pherkad), which seem to march in a circle like sentries around Polaris, the North Star.
Historical Observations
The Ursids are poorly observed and have produced at least two major outbursts in the past 70 years: one in 1945 and another in 1986. Several lesser rate enhancements have been reported from 2006 to 2008, and in 2011, 2014, 2015, 2017, and 2020. These events might have been influenced by the relative proximity of the shower’s parent comet, 8P/Tuttle, which circles the sun in a 13.6-year orbit.
Observing Tips
The peak of this meteor display usually occurs during the overnight hours of December 21-22. The Ursids are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. On the morning of maximum, hourly rates of between 5-10 Ursids may be seen.
These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky.
On the morning of maximum, hourly rates of between 5-10 Ursids may be seen. Plunging through the Earth’s atmosphere at 22 miles (35 km) per second, the Ursids produce mostly medium-speed meteors.
Very little activity will be seen away from the night of maximum activity. The Ursids appear to radiate from the constellation Ursa Minor, also known as the “Little Dipper”.
Enhanced Activity?
No unusually strong activity has been forecasted for 2025. However, a Dutch American meteor calculator, Peter Jenniskens, lists an encounter with a dense filament of meteoric material on December 22 at 12:39 a.m. EST.
An hourly rate of 25 listed by Jenniskens is similar to values indicated for the 2021-24 returns, although no such enhancements were reported in those years.
French meteor expert Jérémie Vaubaillon has performed calculations using computer simulations that show that the densest section of the stream is in the vicinity of Earth on December 22 at around 5:00 a.m. EST, but with no pronounced peak. Still, if you’re up before dawn breaks that morning and your skies are clear, you might want to step outside and check the northern sky.
December’s nearly new moon gives a perfect chance to end the year on a positive note, if skies are clear enough to see what the Ursids may do this time.
Joe Rao serves as an instructor and guest lecturer at New York’s Hayden Planetarium. He writes about astronomy for Natural History magazine, Sky & Telescope, and other publications.
