Draconid meteor shower at a glance
| Detail | Value |
|---|---|
| Activity window | about October 6 to October 10 |
| Peak | around October 8–9 |
| Zenithal hourly rate (ZHR) | usually about 10 or less; variable |
| Radiant | Draco, near the dragon’s head |
| Parent body | comet 21P/Giacobini–Zinner |
| Entry speed | about 20 km/s |
The window and peak follow the calendar of the International Meteor Organization (IMO). For the current list of all showers, see the meteor shower calendar.
A shower of surprises
In most years the Draconids produce only a handful of meteors per hour, and many observers do not notice them at all. But the shower has a dramatic history. In 1933 and 1946 observers in Europe saw meteor storms, with rates reported in the thousands per hour for a short time. Smaller but strong outbursts have been seen in other years, including 2011.
The reason is the parent comet. Comet 21P/Giacobini–Zinner orbits the Sun about every 6.6 years, and its debris has not spread evenly along its orbit. Instead, it forms fairly narrow trails. When Earth passes through a fresh, dense trail, rates jump. In other years Earth misses the dense parts and the shower is barely noticeable.
Slow meteors
Draconid meteoroids catch up with Earth from behind rather than meeting it head-on, so they enter the atmosphere slowly, at around 20 km per second. Compare that with the Orionids or Leonids, which arrive at more than three times that speed. Slow meteors look leisurely and are often faint. If you see a gentle, unhurried streak coming from the north in early October, it is a good Draconid candidate.
Where and when to look
The radiant lies in the northern constellation Draco, near the small group of stars that forms the dragon’s head, not far from the bright star Vega. For observers at mid-northern latitudes the radiant is highest in the early evening, soon after it gets dark. That makes the Draconids one of the few showers that favor the evening over the hours before dawn.
From the Southern Hemisphere the radiant stays low or below the horizon, so the shower is essentially a Northern Hemisphere event.
Moonlight and the Draconids
Because normal Draconid rates are so low, moonlight matters a great deal. A bright Moon in the evening sky can hide nearly all of them. Check the moon phases for early October and the moonrise and moonset times where you live. If an outburst is forecast, even a moonlit sky may still show some activity, but darker is always better.
Viewing tips
- Start soon after dark. The first hours of the night are usually the most productive.
- Face north, then look up. Keep a wide view of the sky around and above the radiant.
- Find dark skies. With so few meteors, every bit of light pollution counts.
- Watch for news of predictions. Meteor researchers publish outburst forecasts ahead of time. A predicted encounter with a dust trail is the main reason to make a special effort.
- Bring warm clothing. October nights can be cold in the north.
- Use only your eyes. A reclining chair and patience matter more than any equipment.
October also brings the Orionids later in the month, so a clear night in early October is good practice. For what else is visible, see the sky tonight.