This radio signal from deep space reveals a (too) technological origin

Everything seemed to indicate that it was a phenomenon from deep space. An ultra-fast radio signal, detected in Australia, had all the hallmarks of a fast radio burst—those enigmatic flashes that have puzzled researchers for years.

Yet this time, the surprise came from much closer.


Astronomers spotted this signal using the ASKAP radio telescope, a cutting-edge instrument located in the Australian desert. Its minuscule duration—less than 30 nanoseconds—immediately caught their attention. It's far shorter than what is usually observed, prompting researchers to dig deeper.

By tracing the origin of this pulse, scientists discovered it didn't come from a distant galaxy... but from a NASA satellite launched in the 1960s, now inactive. Named Relay 2, it still orbits about 2,800 miles (4,500 km) above our heads.

So this wasn't a cosmic message, but rather an unintentional emission. Two explanations are being considered: an electrostatic discharge due to accumulated electricity, or the impact of a micrometeorite on the satellite's surface. Such events can produce a brief radio spark, detectable from Earth.

Even though this signal isn't of astrophysical origin, it remains valuable. It shows just how difficult it can be to distinguish between celestial objects and human-made artifacts. This pushes scientists to be even more cautious when interpreting detected signals.