The Draconids meteor shower
Key facts
- Peak
- around 8–9 October
- Active
- about 6–10 October
- Rate at peak (ZHR)
- usually under 10, but capable of rare storms
- Speed
- 20 km/s
- Radiant
- Draco (near the Dragon's head)
- Parent body
- Comet 21P/Giacobini–Zinner
Dates shift slightly from year to year. This year's peak is in the events calendar.
Most years the Draconids are barely noticeable, with just a few meteors an hour. But this is the shower with the wildest mood swings of all. On rare occasions it has erupted into a true meteor storm, with meteors falling faster than anyone could count.
The shower is sometimes called the Giacobinids, after its parent comet. Comet 21P/Giacobini–Zinner was discovered in 1900 by Michel Giacobini at Nice Observatory in France, and found again in 1913 by Ernst Zinner in Bamberg, Germany. It is a small comet that orbits the Sun about every six and a half years. Its orbit passes very close to the Earth's, so when the Earth arrives just after the comet has passed, we can run straight through fresh, dense trails of dust.
That is exactly what happened in 1933 and 1946. On both occasions observers saw thousands of meteors in an hour. The 1933 storm was seen across Europe, and the 1946 display was seen across North America despite a bright Moon, and was also tracked by radar in England, one of the first times a meteor shower was studied that way. Since then there have been several smaller outbursts. In 2011 astronomers predicted that the Earth would cross trails laid down by the comet in the late nineteenth century, and observers in Europe and the Middle East recorded rates of several hundred an hour at the peak, with radar detecting even more. Another short outburst was seen in 2018. These successful predictions show how well scientists can now model the way comet dust spreads out in space.
The slowest shower. Draconids hit the atmosphere at only about 20 km/s, making them the slowest of the major showers. Slow meteors are easy to follow by eye and often look leisurely, crawling across the sky. The particles also seem to be especially fragile, crumbling high in the atmosphere, so few produce long-lasting trains.
What to expect. In a normal year, expect very little: perhaps a handful of meteors an hour, even near the peak. The interest lies in the chance of something more. Specialists calculate when the Earth will pass close to the comet's old dust trails, and those predictions appear in meteor calendars ahead of time. If an outburst is forecast, it is well worth watching, because the peak can be brief and dramatic.
Viewing from the UK. The UK is well placed for the Draconids. Draco is a circumpolar constellation from Britain, which means it never sets. Unusually, the radiant is highest in the evening rather than before dawn, so the best time to watch is soon after dark, from nightfall until about midnight. That makes the Draconids a good shower for families, as there is no need to stay up into the small hours. The Dragon's head is a small quadrilateral of stars not far from the bright star Vega, high in the north-west in the evening.
Viewing worldwide. The Draconids are a northern hemisphere shower. Europe, North America and northern Asia have the radiant well placed. From the tropics it is low, and from most of the southern hemisphere it never rises.
Peak timing varies from year to year, and outbursts depend on where the Earth meets the comet's trails, so check current predictions each October.
Viewing tips
- Watch in the evening, when the radiant in Draco is highest from the UK.
- Check meteor calendars for any predicted outburst and its expected time.
- Look high in the north-west, near the bright star Vega, to find the radiant.
- Expect slow, leisurely meteors that are easy to follow with your eyes.
- Be patient: most years are quiet, but a storm year is unforgettable.
Read about the parent: Comet Giacobini–Zinner, and the other comets behind meteor showers.