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

A strange purple object aboard the ISS sparked alien fears online, but NASA revealed it was a potato experiment. It shows how microgravity can turn ordinary plants into bizarre shapes.

Scientists have uncovered a surprising way to study the harsh space weather around young M dwarf stars. Mysterious dips in starlight turned out to be massive rings of plasma swirling in the stars’ ...

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

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 ...

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

A strange, tentacled object that went viral online was revealed to be a space-grown purple potato. Astronaut Don Pettit ...

Debunking alien claims matters, but so does telling richer, more compelling stories about how humans shaped their own past.

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

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 ...