Add Yahoo as a preferred source to see more of our stories on Google. Donald Trump's pledge to release official files relating to UFOs has intrigued conspiracy theorists who suspect the US government ...

July 29 (UPI) -- A California woman's doorbell camera captured a video of a mysterious figure that has some residents speculating about alien activity. Jessica Ortiz shared footage to social media ...

A NASA image from Mars has reignited an old question online: are some of the strange patterns on the Red Planet really signs ...

Elon Musk has turned a long-running joke about being an extraterrestrial into a central part of his public persona, even as he argues that humanity may be the only intelligent life in the universe.