Meteor Burst Communications

Back before satellites, to transmit radio waves over really long distances folks bounced them off the ionosphere—a layer of charged particles in the upper atmosphere. Unfortunately this layer only reflects radio waves with frequencies up to 30 megahertz. This limits the rate at which information can be transmitted.

How to work around this?

METEOR BURST COMMUNICATIONS!

On average, 100 million meteorites weighing about a milligram hit the Earth each day. They vaporize about 120 kilometers up. Each one creates a trail of ions that lasts about a second. And you can bounce radio waves with a frequency up to 100 megahertz off this trail.

That’s not a huge improvement, and you need to transmit in bursts whenever a suitable meterorite comes your way, but the military actually looked into doing this.

The National Bureau of Standards tested a burst-mode system in 1958 that used the 50-MHz band and offered a full-duplex link at 2,400 bits per second. The system used magnetic tape loops to buffer data and transmitters at both ends of the link that operated continually to probe for a path. Whenever the receiver at one end detected a sufficiently strong probe signal from the other end, the transmitter would start sending data. The Canadians got in on the MBC action with their JANET system, which had a similar dedicated probing channel and tape buffer. In 1954 they established a full-duplex teletype link between Ottawa and Nova Scotia at 1,300 bits per second with an error rate of only 1.5%.

This is from

• Dan Maloney, Radio apocalypse: meteor burst communications, Hackaday, 2025 May 12.

and the whole article is a great read.

There’s a lot more to the story. For example, until recently people used this method in the western United States to report the snow pack from mountain tops!

The system was called SNOTEL, and you can read more about it here:

• Dan Maloney, Know snow: monitoring snowpack with the SNOTEL network, Hackaday, 2023 June 29.

Also, a lot of ham radio operators bounce signals off meteors just for fun!

• Robert Gulley, Incoming! An introduction to meteor scatter propagation, The SWLing Post, 2024 January 17.