One Pluto year equals 248 Earth years. At 1473 miles in diameter—about half the width of the United States—Pluto is the ...

New research suggests that billions of years ago, Pluto may have captured its largest moon, Charon, with a very brief icy ...

The New Horizons spacecraft, launched on January 19, is on a 10-year journey to explore Pluto, its moons and the Kuiper Belt. (Full story) 2003 UB313's elongated orbit is 97 times as far from the ...

Billions of years ago, in the frozen edges of the solar system, a violent impact shaped one of space’s oddest pairs. Instead of a typical planet-moon setup, Pluto and Charon became a binary system.

Nitrogen is heated and cooled as Pluto rotates. A New Horizons image of Pluto and its moon Charon revealed more surprises about the dwarf planet and its orbiting moon. Click on the hand to see why ...

A planet's gravity comes from its mass — more massive objects have ... At just two-thirds the diameter of our moon, Pluto has such weak gravity that your baseball could clear the 455-foot ...