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 ...

Astronomers studying the Kuiper Belt have detected a strange distortion that could point to an unknown planet lurking far beyond Neptune.

Add Yahoo as a preferred source to see more of our stories on Google. An illustration showing Planet Nine, a hypothetical, undiscovered planet in our solar system. New research now suggests the ...

There may be a warp in the Kuiper Belt, possibly caused by “Planet Y” — a Mercury-to-Earth-sized world that orbits the sun way beyond the orbit of Neptune. Is there a mysterious “Planet Y” orbiting ...

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 ...

A new model that incorporates data gathered by the JWST could help scientists understand the composition and mass of objects in the distant Kuiper Belt and beyond.

It is a question that feels like it should have a straightforward answer: how many planets are there in our solar system? Since Pluto was relegated back down to dwarf planet status, almost everyone ...

Is there a massive undiscovered planet on the outer reaches of the Solar System? The idea has been around since before the discovery of Pluto in the 1930s. Labelled as planet X, prominent astronomers ...

Ian Whittaker does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...

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 dubbed ...