A new study has proposed the existence of Planet Y, an alternative Planet Nine candidate that is smaller and closer to Earth ...

A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and ...

Thirty years ago this week, two Swiss astronomers announced that they had spotted the first known planet orbiting a Sun-like ...

Astronomers are investigating a potential hidden planet, dubbed Planet Y, far beyond Neptune. Its gravitational pull is ...

— -- Astronomers on Monday reported the discovery of an Earth-like planet outside the solar system whose size and distance from its own star put it in the "habitable" zone and make for a surface ...

A newly discovered space rock will zoom safely by Earth later today (Oct. 15) at only about a quarter of the average distance ...

Astronomers have spotted a free-floating ‘rogue’ planet, named Cha 1107-7626, that is going through a massive growth spurt, ...

It's not the first time there have been claims of signs of life on Mars, so why are scientists particularly thrilled now?

“This finding by Perseverance …is the closest we have ever come to discovering life on Mars,” said acting NASA administrator ...

Space scientists look back on three decades of exoplanet discoveries—from rows of massive ‘super-Earths‘ to worlds with ...