A planet with twice Earth's gravity produces creatures with different skeletal requirements, different muscular architecture, ...

Scientists can't fully agree on what GJ504b actually is. It may be a massive planet or a brown dwarf, a mysterious class of ...

DETROW: I mean, it seems like a lot of people, apparently including film director Steven Spielberg, believe the existence of aliens would cause people to lose or at least deeply question their ...

A rare visitor from another star system prompted SETI to hunt for alien technology, but the mysterious object appears to be a ...

There are "vast hidden magma systems" inside of Mars, scientists say – and it could have major implications for the search ...

A strange interstellar comet discovered last year and speculated by a prominent astronomer to be an alien spacecraft could be ...

An interstellar comet that blazed past the sun and swung by Earth last year could be nearly three times older than our solar ...

As for those salt clouds, the salt is not table salt or even Pink Himalayan Rock Salt, though that would go splendidly with ...

Even at this early stage in our spacefaring age, humanity has already begun sending probes that will eventually reach other ...

James Webb has revealed that the sunrise and sunset sides of WASP-121 b have surprisingly different atmospheres.

Do not shout ‘alien!’” Amid surge of public interest in UFOs or UAP, one group updated its rules for how news of extraterrestrials should be revealed.

The TRAPPIST-1 system, located about 41 light years from Earth, has been a focal point of much exoplanetary discussion—mainly because it has seven confirmed planets orbiting a dim M-dwarf star. Two of ...