Meteor Antenna

17th February 2016
Over the Christmas break I was reading up on using distant FM radio stations to detect and count meteors. The technique is called forward scattering. It makes use of the reflection of distant FM signals from meteor plasma trails. Meteors create momentary plasma trails at altitudes ~100km, which reflect in the ~100MHz range for up to 1-2 seconds. Fortunately there are a few gaps in the local FM bands and I could identify some distant potential radio stations with power outputs ~80 kW. So I built a tunable and very directional Yagi-Uda antenna. First I wanted to hear it for myself before setting up a computer, so for a few nights I listened to the hiss of an empty FM band for 1-2 hours at a time in the very early morning and then finally 2 seconds of rock music, then it was gone. I was tuned to a rock station in Canberra (467 km NE) - the signal had been reflected back from space by a meteor trail somewhere over the Australian Alps. I've now set up a computer to do the listening and shifted the focus to more distant stations in Rockhampton QLD, which is 1,686 km N-NE of my home, and picking up meteors over central NSW.

Leave a comment

Your Name
Your Email
Your Comment
No info required here, please press the button below.