Back in the 1980’s, a now-defunct magazine called Science Digest held a contest to name Planet X — the still-undiscovered world that astronomers believed might lie out beyond Pluto. One of the best ...

Pluto may have been demoted to non-planet status, but it still commands a court of five moons, as is fitting for the king of darkness; after all, Pluto is the Roman equivalent of the Greek God Hades.

Pluto may be small, but it has one of the most unusual moons in the solar system. Charon is so big compared to Pluto that the two worlds orbit each other like a pair. In this video, we explain why ...

The discovery of another moon around Pluto is exciting news for planetary science, but it's also likely causing some anxiety for the team in charge of New Horizons, a spacecraft set to be the first ...

Planets, moons and other celestial bodies are named according to rules established by the International Astronomical Union (IAU). Pluto did not have any rules for naming surface features because, ...