The Chi Orionids meteor shower
Key facts
- Peak
- around 2–10 December (historically listed)
- Active
- late November to mid-December
- Rate at peak (ZHR)
- about 2–3
- Speed
- 28 km/s
- Radiant
- Orion and Taurus (near the star Chi¹ Orionis, in Orion's raised club)
- Parent body
- The Taurid complex (linked to comet 2P/Encke)
Dates shift slightly from year to year. This year's peak is in the events calendar, and the meteor-shower planner shows how high the radiant climbs from where you live, night by night.
The Chi Orionids are slow December meteors from the border of Orion and Taurus. They are the tail end of the Taurid complex, the vast, ancient stream of debris that gives the Northern and Southern Taurids of October and November.
The Taurid complex. The best-known member of the complex is comet 2P/Encke, which orbits the Sun every 3.3 years. Over thousands of years, planetary gravity has spread Encke's debris and that of related bodies into a broad band, so Earth spends several months passing through it. As the season goes on, the radiants drift east through Aries and Taurus, and by early December they reach the border of Orion. Observers gave this late activity its own name, the Chi Orionids, with northern and southern branches.
A change of view. Like other weak showers near the ecliptic, the Chi Orionids were later merged into a broader source. Observers now count December activity from this direction as part of the Antihelion Source, which takes over from the Taurids at the start of December. Specialists still study the Chi Orionids as part of the Taurid complex.
What to expect. Two or three slow meteors an hour, at about 28 kilometres per second, from a broad area. Like the Taurids, they can include bright, slow fireballs. Early December is also the start of the Geminids, which are faster and more numerous, so most meteors from this part of the sky will be Geminids by the second week of the month.
Viewing from the UK. Excellent. Orion and Taurus are high in the south around midnight in December, and nights are at their longest.
Viewing worldwide. The radiant is north of the celestial equator but visible from most of the world, including much of the southern hemisphere.
Viewing tips
- Watch around midnight, when Orion is high in the south.
- Find Orion's raised club, above Betelgeuse, towards the horns of Taurus.
- Look for slow meteors, which are easy to tell from fast Geminids.
- Keep a camera running for slow Taurid-family fireballs.
- Dress warmly for a long December night.
Read about the parent: Comet Encke, and the other comets behind meteor showers.