Because the solar system's contents formed from a disk around the sun, we would expect the orbits of everything orbiting the sun to keep relatively close to the plane of that disk. However, some don’t ...

Planet 9 sits at the edge of scientific imagination, promising either an epic expansion of the Solar System or a lesson in ...

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 ...

Planet Nine is a theoretical planet in the outer solar system that has proved to be extremely hard to find. | Credit: Shutterstock Some experts believe that we could be just a few years away from ...

Far beyond Neptune, something heavy appears to be tugging on the outer solar system, bending the paths of distant icy worlds in ways gravity alone should be able to explain. Planet 9, still invisible ...

Researchers at the California Institute of Technology (Caltech) have found new evidence that further suggests there is a ninth planet in our solar system. Nicknamed "Planet Nine," researchers said ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. Is there an unseen planet — a "planet X" or "Planet Nine" — ...

Mike Brown is convinced that beyond Neptune, at the far reaches of our solar system, there's an unseen giant planet. "This is the 5th largest planet in our solar system, lurking out there, waiting to ...

A leading scientist has told Newsweek about new evidence supporting the existence of a secret ninth planet lurking at the edge of our solar system. This hypothetical extra planet, often referred to as ...

Breakthroughs, discoveries, and DIY tips sent six days a week. Terms of Service and Privacy Policy. Almost a decade after astronomers proposed the existence of Planet ...

Some experts believe that the solar system's hypothetical ninth planet could be just a few years away from being discovered. If this is the case, how long would it take for humans to send probes to ...