Six Beacons Waiting for a Fall Zone I Can't Predict

The fireball report came in at 11:34 PM—somewhere northwest of Red Deer, visual magnitude -8, possibly fragmenting. Weather radar showed texture on the 05:40 UTC sweep, which meant pieces large enough to track were already on the ground. Forty-eight hours to recover anything scientifically uncontaminated. Seventy-two if the forecast holds and we don’t get rain.

By midnight I had the Yagi assembled—three elements on a PVC boom, fed with RG-58 coax terminated in a BNC. The same antenna I built for tracking balloon payloads through farm country works just as well for fox hunting, which is what radio direction finding is called when you’re searching for transmitters instead of meteorites. Tune to 144.390 MHz, watch the S-meter, use your body as a Faraday shield to sharpen the null. Standard ham radio sport, except nobody plays this game across muskeg in the dark chasing rocks that fell from the asteroid belt.

The theory sounded clean when I sketched it two weeks ago, right after finding that quartz specimen on Highway 22. Meteorites are just geology that arrives suddenly. If you can document locality provenance for terrestrial minerals, you can do it for extraterrestrial ones. If you can track APRS beacons through stratospheric drift, you can track them through ground scatter. Combine the skills. Build the infrastructure.

What I built: six witness plates—aluminum discs 15 centimetres across with piezo impact sensors and APRS trackers, each beacon transmitting position and battery voltage every five minutes on 2-meter band. Total weight: 340 grams including the LiPo cells. Weatherproof rating: IP67. Battery life at -30°C: maybe four days.

What I didn’t build: a way to predict where to put them.

Strewn fields follow ablation physics. The meteoroid enters atmosphere at 12-20 km/s, fragments from thermal shock, scatters pieces in an elliptical pattern aligned with the flight path. Smaller fragments decelerate faster, fall shorter. The big pieces—anything over a kilogram—punch through to terminal velocity and land at the far end of the oval. You’re not hunting a point impact. You’re triangulating across a zone that might span 15 kilometres.

The fireball reports give rough azimuth. Weather radar confirms fragmentation altitude—this one broke up around 18 kilometres based on the echo pattern. But the math requires knowing entry angle, initial velocity, ablation coefficient, atmospheric density profile. Variables I don’t have, extracted from visual observations by people who were startled by the sky exploding.

So the witness plates are still in the garage. They work—I’ve tested them with a hammer against concrete, verified the beacon triggers and transmits. But deploying them requires answering: where?

Observed meteorite falls average eleven per year globally. The Meteoritical Bulletin Database lists 1,273 confirmed falls since 861 CE. Alberta has recorded maybe a dozen. Your chances of being near a fall zone when it happens are effectively zero. What this hobby actually requires isn’t radio equipment or field geology—it’s pre-positioning sensors in areas where meteorites might fall, weeks or months before the event, covering enough territory that probability starts working in your favour.

Hundreds of sensors. Landowner permissions. Maintenance schedules. Solar charging to extend deployment. A monitoring system to parse telemetry and recognize impact signatures. The infrastructure scales up immediately from hobby to research program, and I’m sitting here at 1:20 AM with six witness plates and no prediction model that tells me where tonight’s fireball dropped its payload.

The Chelyabinsk hunters had it easy—they followed holes melted in snowdrifts by fragments still radiating atmospheric entry heat. Simple visual tracking. Alberta’s spring melt season gives you a narrower window. Rain starts oxidizing iron-nickel within hours. The fusion crust—that glassy ablation layer that proves extraterrestrial origin—weathers fast.

Seventy-one hours left on the contamination clock, assuming no precipitation. No sensors deployed. No target coordinates except “northwest of Red Deer,” which covers roughly four thousand square kilometres of crown land, private ranch, and forest.

The Yagi leans against the workbench. The witness plates sit in their weatherproof cases. The equipment is ready. The hobby is waiting for a problem I can’t engineer my way around: I need to be lucky about where rocks fall from space, and luck doesn’t respond to better antennas.