Just because Pluto was ruled out as a planet in 2006 doesn’t mean our solar system only has eight planets. The search for Planet Nine is far from over as scientists continue to uncover clues ...

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 ...

The small world was found during a search for the hypothetical Planet Nine, and astronomers say the next time it will reach its closest point to the sun is in the year 26186. By Kenneth Chang Kenneth ...

Astronomers have long speculated about the existence of a mysterious planet lurking far beyond Neptune, a world several times larger than Earth whose gravity could be shaping the outer reaches of our ...

Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar system was touted more than a century ago. But ...