What is Radio Meteor Scatter
Radio meteor scatter is a radio propagation phenomenon where radio waves are reflected or scattered by the ionized trails left behind by meteors as they burn up in the upper atmosphere — typically at altitudes of 80–120 km (in the E region of the ionosphere).
Here’s a clear breakdown:
🧠 How it works
- A meteor enters the atmosphere at high speed and ionizes the air along its path, creating a short-lived plasma trail of free electrons.
- This ionized trail can reflect radio waves, especially in the VHF range (30–300 MHz).
- If a transmitter and receiver are both below the horizon of each other, they can communicate briefly via the reflection from that meteor trail.
- The reflection lasts from a few milliseconds (underdense trail) up to a few seconds (overdense trail) depending on the size and velocity of the meteor.
📡 Typical frequencies
- Most effective between 30 and 150 MHz, e.g. 50 MHz (6 m band) or 70–144 MHz.
- Below ~30 MHz the ionospheric reflections dominate, and above ~200 MHz the wavelength is too short for efficient reflection from typical meteor trails.
🔭 Applications
- Amateur radio operators use meteor scatter to make long-distance contacts (up to 2000 km) even when other propagation modes are poor.
- Meteor radar systems and radio astronomy projects use it to:
- Detect meteors invisible to optical systems.
- Measure meteor rates, velocity, and ionospheric conditions.
🪄 What you can detect
With a simple setup — such as an antenna, SDR receiver, and a constant VHF transmitter (beacon or FM station) located several hundred km away — you can:
- See “pings” or bursts of reflected signals on a waterfall display.
- Record meteor counts and even estimate meteor shower activity (e.g. Perseids, Geminids).
⚙️ In summary
| Property | Description |
| Cause | Ionized meteor trail in upper atmosphere |
| Altitude | 80–120 km |
| Duration | Milliseconds to seconds |
| Range | 500–2000 km |
| Best frequency range | 30–150 MHz |
| Used for | Meteor detection, long-distance VHF communication |