Advanced Meteor Observing
It's fun to record what you see.
Meteor studies have relied heavily on amateur observers for more than a century. They still do. Many efforts in the past, however, floundered because of one big problem: the observers didn't acquire their data in a consistent way that made it useful. The number of meteors you see depends heavily on the amount of light pollution at your site, the altitude of the shower's radiant, the size of your unobstructed view, and other factors. These variables need to be recorded and controlled as well as possible, so that corrections can be applied to make everyone's counts intercomparable.
Since its founding in Belgium in 1988, the IMO has done an excellent job of standardizing this formerly disorganized field worldwide. Amateurs now have a professional-quality organization to set guidelines for observers, receive their data, reduce it, analyze it, and publish it rapidly.
The true measure of a meteor shower's intensity — the standard to which every observer's count is reduced — is the zenithal hourly rate, or ZHR. This is the number of meteors that a single observer would see per hour if the shower's radiant were at the zenith and the sky were dark enough for 6.5-magnitude stars to be visible to the naked eye. A successful meteor campaign results in a "shower profile," a graph of ZHR versus time. If enough observers spaced around the globe can keep the shower under 24-hour watch for many days running, a full record can be made of all its activity. This in turn provides a cross-section of the meteoroid swarm in space — invaluable for studies of these closest, yet best hidden, pieces of the solar system.
But to create a good shower profile, one with small error bars, thousands or even tens of thousands of meteor observations are needed. So everyone who turns out and uses the methods described on the following pages will be filling a real need.
