Scientists have unlocked one of the solar system's many secrets from an unexpected source: a planetarium show.

It's an evocative idea that has long bedeviled scientists: a huge and mysterious planet is lurking in the darkness at the ...

Scientists' hunt for a mysterious planet at the edge of our solar system might have turned up results. A US-trio appears to ...

A recently discovered celestial body is rewriting our knowledge of the Kuiper Belt and maybe challenging the existence of the ...

U.S. astronomers hunting for "Planet Nine" have instead stumbled on what appears to be a new dwarf planet in the solar system's outer reaches.

Scientists hunting for the hypothetical Planet Nine have discovered a potential new dwarf planet, 2017 OF201, in the outer ...

They said: ‘The discovery of 2017 OF201 is significant because it’s found in a region of the Solar System thought to be empty ...

Some astronomers say the strange, clustered orbits of icy rocks beyond Neptune indicate that something big is out there, ...