Billions of years ago, another planet smashed into Earth. An event of this epicness could have created our Moon. It also could have brought alien life to our planet. What evidence of this planet still exists on Earth today?

To travel between solar systems, a spacecraft would need extremely sophisticated – if not impossible – technology.

Scientists are listening in on sperm whale conversations and studying Earth's strangest microbes to prepare humanity for first contact with extraterrestrial life.

Astronomer Jon Willis warns that alien signals could be passing Earth unnoticed because humans are searching on the wrong scales, with the wrong assumptions about life and intelligence.

As its name suggests, Alien: Earth imagines what would happen if the Xenomorph wound up on our planet. Here, it arrives as part of the cargo of the USCSS Maginot, a Weyland-Yutani research vessel that crash lands in New Siam, Prodigy City, named after Weyland-Yutani rival Prodigy Corporation.

When it comes to DC Comics, there are an overwhelming number of aliens on Earth, including some of the most powerful heroes in comics. This has been true since the start, as the first actual superhero that DC introduced was an alien sent to Earth, and ...