The Comae Berenicids meteor shower
Key facts
- Peak
- around 20–23 December
- Active
- early December to late January
- Rate at peak (ZHR)
- about 3
- Speed
- 65 km/s
- Radiant
- Leo Minor and Leo, drifting east towards Coma Berenices during the season
- Parent body
- Unknown
Dates shift slightly from year to year. This year's peak is in the events calendar.
The Comae Berenicids are a long, weak shower of fast meteors that runs from the time of the Geminids to the end of January. Their name and their definition have both changed over the years.
A confusing history. In the 1950s Fred Whipple, studying photographic meteor orbits, identified a stream from Coma Berenices, Berenice's Hair, in December and January. Later work by visual observers, radar and video networks showed a longer, more complex pattern. Much of the activity in December comes from a radiant in Leo Minor, which specialists call the December Leonis Minorids, and the radiant then drifts east towards Coma Berenices over the following weeks. The standard list of visual showers groups the whole complex under the old name, Comae Berenicids, with a maximum around 20 to 23 December.
The parent. No parent body has been identified. The very high speed of the meteors, about 65 kilometres per second, means the meteoroids travel on orbits that meet Earth almost head on, as is typical for long-period comets.
What to expect. Around three meteors an hour, swift and often faint, with an occasional bright one. The shower is active during the Geminids and the Ursids, and during the Quadrantids in early January, so it often goes unnoticed.
Viewing from the UK. Good. Leo and Leo Minor rise in the late evening in December and are high in the south before dawn. The long nights of midwinter give plenty of time for observing.
Viewing worldwide. The radiant is in the northern sky, but low enough in declination to be seen from most of the southern hemisphere, though it stays low there.
The Comae Berenicids are a good example of the many faint streams that make up the background of winter meteors.
Viewing tips
- Watch in the hours before dawn, when Leo is high in the south.
- Find the Sickle of Leo and look north towards Leo Minor.
- Expect very fast meteors, much quicker than Geminids.
- Note the direction of each meteor to separate this shower from the Ursids.
- Dress for a long midwinter night.