Pluto

The long-simmering argument about Pluto's planethood has just flared up again.

The names of explorers and the authors of journeys make up some of the first feature names for Charon.

A thick, gooey, asphalt-like layer could lie beneath Pluto's crust.

There may be a lot more potentially habitable worlds zooming through the cold depths of deep space than scientists had thought.

Hydrocarbon particles in Pluto's atmosphere are responsible for the dwarf planet's surprisingly low temperatures, a new study suggests.

A grassroots movement seeks to build momentum for a second NASA mission to the outer solar system, a generation after a similar effort helped give rise to the first one.

Pluto's surface hosts blades of ice that soar to the height of skyscrapers — and researchers have narrowed down exactly how the dramatic features form.

NASA's New Horizons spacecraft may double its pleasure during its next deep-space flyby 16 months from now.