The surface of Mars looks like an empty red wasteland. But if you look a bit closer, the remnants of an ancient alien civilization begin to take shape. At least, that's the conclusion of George J.

Is intelligent alien life really out there? With powerful telescopes identifying more potentially habitable planets each year ...

The Search for Extraterrestrial Intelligence (SETI) focuses on finding technosignatures—potential signs of alien technology. If we look carefully, we might have a chance at detecting their ...

A team of astronomers claims to have sniffed out a “biosignature” in the atmosphere of a distant planet called K2-18b. But not everyone agrees that it signals life. An illustration shows what ...