In these science fiction books, extraterrestrial beings are sympathetic, horrifying and everything in between.

(cokada/iStock/Getty Images) Alien megastructures built to harvest stellar energy or alter the orbits of stars may be ...

For months, scientists and the public have squinted their eyes at photos of a blurry smudge to figure out if it’s proof that aliens exist. Discovered in July, 3I/ATLAS is not your average comet – it’s ...

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 ...

Aliens did not visit Earth in the distant past. They didn't build the pyramids or rule ancient Greece from Mount Olympus or teach Mesoamericans how to plant corn. How do I know? Because they didn't do ...

Movies like "Disclosure Day" and "Project Hail Mary" renew our fascination with extraterrestrials and the idea that humankind ...

Trump has ordered a UFO data release. But if aliens exist, what would they think of us? - For generations, human beings have ...

A strange, tentacled object that went viral online was revealed to be a space-grown purple potato. Astronaut Don Pettit cultivated the unusual specimen during a microgravity gardening experiment, ...