A 9th planet in our solar system might be found — and no, it’s not Pluto - Is there another planet out there? Researchers say ...

A ninth planet the size of Neptune may be hidden in the far reaches of the solar system, but the evidence has left some experts skeptical.

Our solar system may have a ninth planet after all, following the declassification of Pluto nearly two decades ago, ...

Astronomers may have found a candidate for Planet Nine. This planet is beyond Neptune. The finding could be the first ...

Discovered in 1930, Pluto was long considered our Solar System's ninth planet, but was unseated in 2006 after the discovery ...

The presence of another planet in the solar system could explain the odd movements of some of the bodies in the Kuiper Belt.

The solar system consists of our star, the sun, and everything bound to it by gravity: the planets Mercury, Venus, Earth, ...

A new look through decades-old data has unveiled some of the most compelling evidence yet of a hidden ninth planet in the far ...