Pluto

After more than a decade of controversy, the debate over the icy world's demotion to "dwarf planet" status shows no sign of stopping

A group of planetary scientists is making the case for a new definition of a planet; this one would include Pluto and most moons. Here's why these researchers think the new definition is better.

Pluto's famous heart-shaped feature is on the road to getting an official name, nearly two years after its discovery.

The New Horizons probe that flew by Pluto in 2015 sent back data suggesting this icy world possesses organics, water and energy, or what scientists consider the necessary ingredients for life.

NASA's New Horizons spacecraft performed a brief engine burn Wednesday (Feb. 1) in preparation for its 2019 flyby of a small, distant object known as 2014 MU69.

Pluto's largest moon, Charon, had a process like Earth's plate tectonics beneath its surface, driven by a freezing ice core that expanded and cracked the little world's crust.