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Best-known meteor shower peaks Aug. 12
When and where to look
Typically during an overnight watch, the Perseids are capable of producing a number of bright, flaring and fragmenting meteors, which leave fine trains in their wake. On the night of shower maximum, the Perseid radiant is not far from the famous "Double Star Cluster" of Perseus. Low in the northeast during the early evening, it rises higher in the sky until morning twilight ends observing.
Shower members appearing close to the radiant have foreshortened tracks; those appearing farther away are often brighter, have longer tracks, and move faster across the sky. About five to 10 of the meteors seen in any given hour will not fit this geometric pattern, and may be classified as sporadic or as members of some other (minor) shower.
Perseid activity increases sharply in the hours after midnight, so plan your observing times accordingly. We are then looking more nearly face-on into the direction of the Earth’s motion as it orbits the Sun, and the radiant is also higher up. Making a meteor count is as simple as lying in a lawn chair or on the ground and marking on a clipboard whenever a "shooting star" is seen. Watching for the Perseids consists of lying back, gazing up into the stars, and waiting. It is customary to watch the point halfway between the radiant (which will be rising in the northeast sky) and the zenith, though its all right for your gaze to wander.
Counts should be made on several nights before and after the predicted maximum, so the behavior of the shower away from its peak can be determined. Usually, good numbers of meteors should be seen on the preceding and following nights as well. The shower is generally at one-quarter strength one or two nights before and after maximum.
A few Perseids can be seen as much as two weeks before and a week after the peak. The extreme limits, in fact, are said to extend from July 17 to Aug. 24, though an occasional one might be seen almost anytime during the month of August.
Photographing meteors
The Perseids are an excellent meteor display to attempt to photograph. Meteor photography is popular. However, the chance of your recording a meteor is enhanced by using a fast lens (f 2.8 or better) and ultrafast film (ISO 400 to 1600). It makes no difference whether the camera is clock-driven or fixed on a tripod.
If your camera has an electronic shutter see if it also has a long time exposure mode that doesn't draw current. Otherwise, put in fresh batteries and plan on replacing them the next day. Mechanical shutters are preferable for long time exposures for this reason.
If all you have is a digital camera, then give it a try. Otherwise, use a film-based camera instead. The reason for this is that digital cameras suffer from thermal noise during exposures of more than a second or so.
In a dark sky, exposures of 10 to 20 minutes long can be made, but should be kept much shorter if background light threatens to fog the film. Slight moonlight, twilight or city glow can be tolerated, as they have little to do with the efficiency of a particular lens-film combination in recording bright meteors.
A successful photograph has many added values if an observer has witnessed and described the same meteor. Also, the chance of obtaining a good meteor picture can be increased by pointing the camera well away from the radiant.
No danger
Many years ago, a phone call came into New York’s Hayden Planetarium. The caller sounded concerned after hearing a radio announcement of an upcoming Perseid display and wanted to know if it would be dangerous to stay outdoors on the night of the peak of the shower (perhaps assuming there was a danger of getting hit). These meteoroids, however, are no bigger than sand grains or pebbles, have the consistency of cigar ash and are consumed many miles above our heads.
The caller was passed along to the Planetarium’s Chief Astronomer who commented that there are only two dangers from Perseid watching: getting drenched with dew and falling asleep!
Whether you plan to take photographs, make detailed meteor counts or just lie back and watch nature put on a show, there should be plenty to see late on the nights of Aug. 11 and 12. As one long-time meteor enthusiast once noted: "Meteor observing is relaxing and enjoyable, potentially dramatic and just plain fun!"
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