Leonids 2001 Results

University of Alberta observatory domes


"Thank you so much for visiting our class on Friday! The kids loved it...they thought it was pretty cool to meet a "real" Astronomer! Thanks again, Janine"

Updated 14 Mar 2011 DC

Here are the results of our test of FM radio meteor detection for the spectacular Leonid Shower of November 2001. On this page we offer:

A picture of the reflection geometry
A description of the equipment we used
Graphs showing the meteor counts for the morning of November 18
Audio files of a meteor reflection

Reflection Geometry

We are located in Edmonton, Alberta. Our equipment was tuned to a radio station in Calgary, Alberta, approximately 300 km almost due south.

The meteor (white streak in picture) travels at a tangent to an ellipse (yellow) with Edmonton and Calgary at its foci.

Radio signals (red) that would not have otherwise reached Edmonton were reflected off the ionization trails of meteors between the two cities.


  1. A 6 element Yagi antenna was connected via coaxial cable to a digitally tuned FM stereo receiver tuned to 92.1 MHz, a Calgary radio station.
  2. An earphone jack in the receiver was connected to the Line In jack on the sound card on a Pentium 1 - 166 MHz computer. The computer had Radio Sky Pipe (free) data logging software installed on it. This software is available from Jim Sky at www.radiosky.com.
  3. These first two steps make up the basic equipment configuration you need to observe meteors with an FM radio.
  4. To record the sound of the Calgary radio signals reflected off meteors, the FM receiver Audio Out was connected to the Audio In on a VCR.
  5. A television was connected to the cable TV in the house and tuned to the local cable TV channel with time and date showing.
  6. The Video Out from the TV was connected to the Video In on the VCR.
  7. The VCR records the sound from the radio and the video time stamp from the cable service. This allows the reflected radio station signals to be recorded on VCR tape alongside the video signal allowing you to know when the signal was detected and to hear the signal all at once.

Graphs of Results

These last three strip charts of data collected with the Radio Sky Pipe software clearly shows the increase in the number of meteors detected over three days during the hours between midnight and 6 am leading up to and including (the last strip chart) the peak activity night.

This graph shows the tally of meteor counts from the peak night.

Hear and See the Results

Push this button to hear what a meteor reflection sounds like. You can hear the station identify its frequency as 92.1 in this recording.

This graph shows the sudden rise in signal strength when you hear the words and music in the recording.


Copyright 1999-2015 by Sky Scan, Edmonton, Alberta, Canada. 

We gratefully acknowledge the financial support of the 

Edmonton Centre of the Royal Astronomical Society of Canada, Department of Physics (University of Alberta)

and the

Natural Sciences and Engineering Research Council of Canada

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