There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as number nine in 2006. Now, a group of international researchers say they may ...

Add Yahoo as a preferred source to see more of our stories on Google. Digital art of distant planet - Dottedhippo/Getty Images On August 24, 2006, our solar system lost a planet. It wasn't by ...

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 ...

In an exciting breakthrough in planetary science, a recent study has increased the likelihood of Planet Nine’s existence by up to 40%. This planet, also referred to as Planet X, has remained an ...

Astronomers have found new evidence that a mysterious ninth planet may be hiding at the edge of the solar system - rewriting what we know about the cosmos again. An international team from Taiwan, ...

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" — ...

Astronomers have been searching for evidence that Planet Nine exists for years Becca Longmire is a digital news writer-reporter at PEOPLE. She has been working at PEOPLE since 2024. Her work has ...

Caltech professor Mike Brown (L) and assistant professor Konstanin Batygin have been working together to investigate distant objects in our solar system for more than a year and a half. The two ...

When I was a kid, the solar system was simple. There were nine planets and they all orbited in more-or-less circles around the sun. This same sun-and-a-handful-of-planets scheme repeated itself again ...