A recent research paper suggests that a planet may exist far beyond Neptune — less than 20 years after the previous ninth planet, Pluto, was demoted. That research paper, accepted last month for ...

Swipe Down for Full Video Story Most of us learned that the Solar System has eight planets. For many years, Pluto made it ...

Scientists may have discovered a dwarf planet far beyond Neptune — an unearthing that may disprove a longstanding theory about the possibility of a giant ninth planet. The dwarf planet's existence ...

There's a new object in the distant reaches of our solar system, and it might just offer clues to a long-standing cosmic mystery. Astronomers have cataloged a frozen minor planet called 2017 OF201, ...

James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...

On August 24, 2006, our solar system lost a planet. It wasn't by cataclysmic destruction, but rather by the vote of the International Astronomical Union, which declared that Pluto, considered the ...

In the cold, dark outskirts of planetary systems far beyond the reach of the known planets, mysterious gas giants and planetary masses silently orbit their stars—sometimes thousands of astronomical ...

New research suggests the moons of Jupiter and Uranus may hint that our planetary neighborhood once had a third ice giant.