To be able to see and listen to meteor echoes, a transmitting and a receiving system are necessary. What is observed are basically
radio signals that are reflected from the plasma trails of the meteors. To do so, the GRAVES French Space Surveillance Radar
located near the city of Dijon (France) is used as a transmitter, and an antenna located on the roof of the Natural History
Museum as receiver.
This technique can also be used to obtain statistical data on meteor numbers, their masses, their trajectories, and the manner
in which ionization trails develop, break up, and decay.
Examples of meteor echoes
These are typical radio signals of meteors as recorded with our system at the Museum (see below). We are looking at a frequency
of 143.05 MHz, the frequency of operation of the transmitter that is used. On the left side is the time in day, hour, minute,
and second of the recorded signal. The larger the extraterrestrial object is, the longer and brighter the actual meteor trail
and reflected radio signal is. In blue is the background signal, whereas in the central part, in white, yellow-orange, to
red, depending of the intensity, are meteor echoes.
See and hear meteors live!Here meteors echoes detected with the system at the Museum are seen and heard in real time, with sounds like bumps, thumps,
Top, x-axis, is the frequency; Left, y-axis, is the time when the detection was recorded; Right, y-axis, is the intensity
of the signal. The more or less continuous lighter blue lines on the right which are due to interferences (i.e., not associated
When to look for meteors?
Meteors can be seen every day of the year, at any time of the day or night, but more so in the early morning, with a
peak at 6 a.m., due to the rotation of the Earth and the direction in which it travels around the Sun.
The frequency at which meteors can be seen also varies during the year. Each year, at the same season, so called “meteor showers”
occur. They form when a large number of small cometary or asteroidal particles enter the Earth’s atmosphere.