Earth's radar signals: Unintentional beacon for alien civilizations
Turns out, Earth's been accidentally broadcasting its presence to nearby aliens for over 70 years.
A new study from the University of Manchester shows that radar signals from airports and military systems have created a kind of "radio signature" that advanced telescopes up to 200 light-years away could pick up.
How Earth is broadcasting itself
Major airports like Heathrow and JFK, along with military radars, send out huge amounts of radio energy—enough for telescopes like the Green Bank Telescope to spot us from neighboring stars.
Have we already been spotted?
Since the Cold War era, these radar emissions have made Earth visible to any civilization with similar tech.
As one researcher suggested, any planet with advanced radar and aviation technology would similarly announce its presence.
So instead of worrying about sending messages into space, maybe we should be asking if anyone's already listening in.