For decades, scientists have been actively searching for signs of extraterrestrial life. Fromradio waves to laser flashes and infrared heat signatures, the hunt for alien technosignatures has captivated both researchers and the public.

Former President Barack Obama said he did not see evidence that aliens “have made contact with us,” after sending social media abuzz by saying aliens were real on a podcast over the weekend.

Planet K2-18b, an apparent water world 124 light years away, has been seen as a promising location in the search for aliens, but telescopes on Earth failed to pick up any radio transmissions

For decades, scientists have searched the skies for signs of extraterrestrial technology. A study from EPFL asks a sharp question: if alien signals have already reached Earth without us noticing, what should we realistically expect to detect today?