The Geminids often steal the spotlight as December’s premier meteor shower, but a lesser-known event, the Ursids, is poised to peak next week – offering a chance for patient skywatchers to witness a subtle yet potentially rewarding celestial display. Unlike the reliably bright Geminids, the Ursids remain largely overlooked, despite their predictable annual occurrence.
The Radiant and Visibility
The Ursids appear to radiate from near Kochab, a bright star in the constellation Ursa Minor (the Little Bear). This proximity to the North Star means the radiant remains visible throughout the night for observers in the Northern Hemisphere. The best viewing window is typically during the late hours before dawn when the radiant is highest in the sky.
The shower’s meteors are medium-speed, entering Earth’s atmosphere at around 22 miles per second. While not particularly spectacular, clear, dark skies – which will be available due to the new moon on December 19th – will significantly improve visibility. Expect a modest hourly rate of 5-10 meteors during peak activity on the night of December 21-22.
Historical Outbursts and Unpredictability
The Ursids have a history of unpredictable behavior. The shower has produced major outbursts in 1945 and 1986, suggesting periods of heightened activity. These events are linked to the parent comet, 8P/Tuttle, which has a 13.6-year orbit. Interestingly, some Ursid peaks have occurred even when Tuttle was at its furthest point from the sun, challenging conventional predictions.
Potential Enhancements in 2023
While no unusually strong activity is explicitly forecast, some experts suggest a possibility of enhanced rates. Meteor calculator Peter Jenniskens predicts a dense filament of meteoric material around 12:39 a.m. EST on December 22nd, estimating a potential peak of 25 meteors per hour. Another expert, Jérémie Vaubaillon, suggests the densest section of the stream will pass Earth around 5:00 a.m. EST on the same day, although without a pronounced peak.
Despite these predictions, the Ursids remain an unpredictable shower. Observers in previous years have not reported enhancements matching Jenniskens’ forecasts.
Worth a Look?
If you’re awake before dawn on December 22nd and have clear skies, glancing at the northern sky could yield a pleasant surprise. The Ursids may not rival the Geminids in intensity, but they offer a quiet, accessible opportunity to appreciate the beauty of space.
The Ursids’ relative obscurity underscores how much remains unknown about meteor showers; their behavior is often linked to unpredictable comet fragments, making accurate forecasting difficult. This uncertainty makes observing them all the more intriguing.
