I once watched a program about finding extraterrestrial life with half an eye. Then it was said that if there were intelligent extraterrestrial life, they could have observed us long ago because our old TV and radio signals are still scattered throughout the universe. Did I misunderstand this? Didn’t listen well? Or are they spreading nonsense?
Answer
Yes, those signals are coming somewhere. But the further away, the weaker the signal, and the harder it is to decode.
The message you heard may have meant that aliens who want to know if there is anything here that interests them should not necessarily search for utterances sent to them, but they can also detect our mutual radio traffic. And they’re right, until we start spreading the information through cables in the ground.
Answered by
Prof. dr. Christopher Waelkens
Astronomy
Old Market 13 3000 Leuven
https://www.kuleuven.be/
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