Powerful radio signal detected near Earth
A long-dead NASA satellite called Relay 2 just sent out a super short, powerful radio signal that was first mistaken for something from deep space.
The ASKAP telescope in Australia picked up the pulse in June 2024 and traced it back—not to a galaxy far away, but to this old piece of space tech still orbiting Earth.
What's the origin of the signal?
Relay 2 launched in 1964 and stopped working by 1967, but it's still circling about 4,500km above us.
Scientists think the burst could have come from either static electricity suddenly discharging on its surface or a tiny micrometeorite hitting it and making a quick plasma flash.
Both ideas have pros and cons—static discharge is tricky because of how brief the pulse was, while micrometeorite hits are rare but possible.
'Space junk' can send out signals strong enough to confuse astronomers
This shows that even "space junk" can send out signals strong enough to confuse astronomers hunting for real cosmic mysteries like fast radio bursts.
As more defunct satellites pile up in orbit, keeping an eye on space debris is getting more important so we don't mix up human-made signals with actual discoveries from the universe.