Astronomers have identified a rare sednoid called Ammonite, an icy object beyond Neptune that offers new insight into the ...

Scientists believe our solar system may be hiding a secret world — and it’s not the famous Planet X :eyes: A new study ...

Jupiter is already the biggest planet by far in our solar system, but new research suggests it was somehow once even larger than it is now. Twice as large, in fact. To put that into context, those ...

Why Can't We Find Planet 9? Deep in the outer reaches of our solar system, far beyond Neptune and Pluto, something massive is hiding in the dark. Scientists call it "Planet 9." For decades, ...

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 ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. The solar system suddenly has a new member. A new object ...

Planet Y is the latest in a series of hypothetical solar system planets that scientists have proposed in recent years, all with slightly different characteristics but collectively believed to be ...

A Hidden Planet: The Missing Piece? To solve these puzzles, researchers have proposed the existence of an undiscovered Earth-like planet in the Kuiper Belt. In a recent study, Dr. Patryk Sofia Lykawka ...

Discover the only planet in our solar system that rotates clockwise. Learn why this 'rebel' planet spins backwards, how a ...

If the solar system does have a Planet Nine, it is a world that was bullied by its larger siblings, exiled to the far reaches of space and only rescued from oblivion thanks to the intervention of ...

(CNN) — The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have ...