It takes Pluto 248 years to complete one journey around the Sun. Humanity has known of its existence for less than half of ...

On July 14, NASA’s New Horizons (http://www.nasa.gov/newhorizons) spacecraft will fly past Pluto, offering the first close-up look at that small, distant world and ...

The accretion of new material during Pluto’s formation may have generated enough heat to create a liquid ocean that has persisted beneath an icy crust to the present day, despite the dwarf planet’s ...

Scientists continue to disagree over how worlds in the solar system should be classified. The argument turns on whether ...

The mystery of how Pluto got a giant heart-shaped feature on its surface has finally been solved by an international team of astrophysicists led by the University of Bern and members of the National ...

Add Yahoo as a preferred source to see more of our stories on Google. Tinged blue by a high-altitude haze, Pluto appears as a receding crescent in this approximately true color composite image ...

Ask almost anyone why Pluto stopped being a planet and you will hear the same confident answer: it was too small. That answer ...