If aliens exist, they could spot Earth from 200 light-years away by airport signals: Study
A study presented at the Royal Astronomical Society has claimed if aliens exist, they could spot Earth from 200 light-years away by detecting airport signals through advanced telescopes. Humans can also spot extraterrestrial life if any "planet with advanced technology and a complex aviation system" unintentionally produces radar signals from the same distance, the study's lead researcher stated.