Armagh Observatory

The Perseid Stream 2002

The Perseid stream is the debris from Comet Swift-Tuttle, and in an average year the Perseids are one of the best meteor showers. Activity from the Perseid shower has already begun, but unless you're a serious meteor watcher, it probably isn't worth bothering to observe for another couple of weeks. Maximum activity is expected on Aug 12th, i.e., the night of the 11th may be best, with activity being reasonable for a few days around that time.

The shower radiant is in Perseus, in fact at the north end of Perseus, so slightly below the "W" of Cassiopeia. This is always above the horizon from the British Isles and so Perseids can be seen at any time of night. But the radiant gets higher as the night progresses, and a higher radiant elevation generally increases the meteor rate. This year the phase of the moon also means that the dark sky will be at the end of the night. On the night of maximum there should be an interval of an hour or two between the moon setting and twilight making the sky too bright. The interval of dark sky will be longer a day or two before maximum. A couple of days after maximum there won't really be any time with dark sky.

One can look anywhere in the sky but as the radiant will be towards the north or northeast, directions such as north and east would be good, and southwest would be a less good direction to look. Perseid meteors are quite fast.

The maximum Perseid rate generally exceeds 100 meteors per hour in a "perfect" sky, although of course most observers usually have a less than perfect sky. No-one has yet found any reason to expect a meteor storm from the Perseids this year.

Last Revised: 2010 February 22nd