This icy world, temporarily named 2017 OF201, could be a distant cousin of Pluto — and scientists mean "distant" quite ...

Astronomers have discovered a mysterious dwarf planet, 2017 OF201, far beyond Pluto. This discovery challenges existing ...

Scientists have discovered a mysterious new object far beyond Neptune, and it could be one of the most distant dwarf planets ...

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

There’s a new frozen oddball orbiting the Sun, and it’s not your average space rock. It’s a planet—a minor one, to be ...

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

Astronomers find evidence of a possible ninth planet beyond Neptune, reigniting the debate about the formation of the Solar ...

Scientists believe such an extreme orbit means the object was pushed and pulled by the gravity of giant planets like Jupiter ...

Cheng, together with graduate students from Princeton University, discovered the potential dwarf planet while searching for ...