ERAU Prescott Observatory

Detecting Meteors with an FM Radio

When a meteor burns upon entry into the atmosphere, atmospheric gases are ionized creating conditions that will reflect terrestrial radio waves that normally can only be received within the line of sight of the transmitter. Distant, over the horizon radio stations normally can not be received except when their signals are reflected back to earth from the ionized gases formed by a meteor.

Detecting Meteors with FM Radio

By using a strong transmitter located over the horizon and a suitably tuned receiver one can detect meteors in the atmosphere.

Antenna used for meteor detection Commercial FM radio stations (87.5 to 108 MHz) provides a very good transmitter that can be used for the detection of the ionized gases formed by a meteor. The abundance of over-the-horizon stations transmitting 24 hours a day ensures that radio detection of a meteor can be heard from a suitably positioned receiver and meteor regardless of the time of day.
6-element beam antenna used for
meteor detection

Strip chart showing two meteors
Strip chart showing two meteors detected

Radio detection rates of meteors tend to be higher than visual observation rates. Meteor particles as small as 3 or 4mm can be visually seen. Meteor particles as small as 0.1mm can be detected by radio observation. Meteor showers will provide many detections. The most intense of these is the Arietids which peak each year around June 8. They can produce up to 100 radio detections per hour.