There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as ...

Though they don't orbit around our sun, sub-Neptunes are the most common type of exoplanet, or planet outside our solar ...

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

A team of astronomers believes they may have spotted a serious candidate for a ninth planet in our Solar System. This object, ...

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 ...

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

The idea that our Solar System is representative of other solar systems hasn't survived the age of exoplanet discovery.

A group of comets with unexplained movements presents a quandary “These objects really look like asteroids in the images,” ...

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.