Scientists believe life on alien worlds may be constrained by the same factors as on our planet.

Robert Smith is convinced the aliens have won. "The invasion has happened—it's all over," says the University of Alberta space historian who teaches a course on the history of extraterrestrials. It's ...

When the Trump administration registered the domains Aliens.gov and Alien.gov in March, UFO conspiracy theorists wondered whether they might finally get answers they’d long awaited. But coming on the ...

Is it the invasion of the genome snatchers? Just in case the idea of aliens walking around in human skin suits wasn’t frightening enough. An outlandish study asserts that aliens might have abducted us ...

At the Telluride Film Festival, Bill Gates compared advanced AI to an alien invasion and urged the United States and China to cooperate on safety, despite significant geopolitical differences.