That’s the signal, originating 11 and a half billion miles away from Earth, of Voyager 1. Way too small for any terrestrial optical telescope to see, but radio telescopes pick it up fairly loud and clear.
“That’s the signal, originating 11 and a half billion miles away from Earth, of Voyager 1. Way too small for any terrestrial optical telescope to see, but radio telescopes pick it up fairly loud and clear.”
...although it takes something like 18 hours for one-way travel of the radio waves. And the bandwidth is now something like 20 baud (20 bits/second)...as in really, really, slow communication. And it’s plutonium battery is even running down.
Incredible spacecraft!