When NASA’s New Horizons spacecraft flew past Pluto in 2015, it revealed a world far more active and complex than scientists expected. Researchers later found evidence that a liquid ocean may exist ...

Pluto has not completed a single orbit since its 1930 discovery. With a 248-year journey around the Sun, the dwarf planet will finish its first full circuit in 2178.

Pluto will complete its first orbit since 1930 in 2178, a historic 248-year space journey that spans generations of humans.

For decades, scientists have theorized that Pluto's unusually large moon Charon formed through a process similar to Earth's moon—a massive collision followed by the stretching and deformation of fluid ...

Pluto may no longer be classified as a planet, but in Flagstaff, its legacy still shines. Scientists, artists and community ...