Meteors are very small bits of debris left from the tail of a comet when it passes through our Solar System. As Earth passes through these debris trails, the tiny meteoroids are swept up in the atmosphere and burn up. It is during this process that the "meteoroid" is known as a "meteor".
The meteor is traveling so fast through Earth's atmosphere, that it actually heats up (ionizes) the air around it which creates a (usually) very brief trail (or "train") behind the meteor.
These ionized trains reflect FM radio signals.
Radio signals travel in a straight line ("line-of-sight"), so if the receiver is far enough away to be over the horizon from the transmitter, nothing but static will be heard. The signal has simply continued off into space at that point.
HOWEVER....I have learned how to LISTEN to meteors!
I have an FM antenna mounted in my backyard, pointing south (toward an FM station 180 miles away) and tilted upwards at 34°. In other words, the antenna is pointed toward the sky in the direction of the radio station.
When a meteor enters Earth's atmosphere between my location and the transmitting station, the radio signal will be reflected off the meteor's trail and "bounced" back toward Earth....in my direction!! These bounced signals can last anywhere from a fraction of a second to a few minutes...depending on the characteristics of the meteor trail.
The annual Geminid meteor shower occurred earlier this month, peaking around the 14th. I was monitoring them, using the above technique, from December 7th - 19th.
Below, is a graph showing the total daily FM meteor reflections for that period. As you can see, the meteor shower peaked around the 15th, then quieted down....
(I get a kick out the look on people's faces when I tell them I enjoy LISTENING to meteors!)
