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If you look up at the sky on a dark night you can sometimes see streaks of light, called shooting stars. These are actually meteoroids burning up in the Earth's atmosphere. Several times a year it is possible to see meteor showers. This is when the Earth passes through the rock and ice left behind by a comet. Some of these showers can have a few meteors an hour, but others have one or two every second. The name of the meteor shower tells us which part of the sky it seems to come from, for example, the Perseid shower seems to come from the constellation of Perseus.
| Shower | Date of Maximum |
Approximate Hourly Rate |
|---|---|---|
| Quadrantids | Jan 3/4 | 100 |
| Lyrids | April 21 | 10 |
| Eta Aquarids | May 5 | 35 |
| Delta Aquarids (south) (north) |
July 29 Aug 6 |
25 10 |
| Perseids | Aug 12 | 80 |
| Orionids | Oct 20-22 | 25 |
| Taurids | Nov 5 | 10 |
| Leonids | Nov 17 | 10 |
| Geminids | Dec 13 | 100 |
| Ursids | Dec 23 | 10 |
Meteorites are meteors that reach the ground. They are usually made of rock or iron. About 40-50 tonnes of meteoroids hit the top of the Earth’s atmosphere every day, but these burn up in the atmosphere and only about a tonne reaches the ground. When a large meteorite strikes the ground it will form a crater. An example of this is Meteor Crater in Arizona. The crater is 1.2 km across and 175m deep. It was made 50 000 years ago by a meteorite only about 50m across.
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Authors: Carolyn Brinkworth and Claire Thomas
Last updated: July 2001