Pluto hasn't been a planet for almost 20 years. In the early 2000s, scientists discovered several objects of a similar size to Pluto. So, during the summer of 2006, members of the International ...

With a diameter of 1,440 miles, Pluto is farthest from the sun. While major planets make roughly circular orbits, Pluto ...

The debate over Pluto’s planetary status has been ongoing since its reclassification as a “dwarf planet” in 2006 by the ...

Though Pluto has formally been considered a dwarf planet for almost two decades, it still has many lessons left for planetary scientists — including hints about how the solar system formed.

On Aug. 24, 2006, the International Astronomical Union (IAU) decided that Pluto wasn't a planet anymore. Instead, Pluto is ...

In Roman mythology, Pluto is the god and ruler of the dead. For a return mission to the dwarf planet, Howett and her ...

NASA's New Horizons probe flew closer to Pluto than any Earth-craft ever has Tuesday, sending back amazing photos of the dwarf planet.

Images of Pluto captured by NASA's New Horizons mission have revealed a new surprise: ice volcanoes. The spacecraft performed a flyby of the dwarf planet and its moons in July 2015, and the ...

Real Image of Dwarf Planet Pluto? A colorful photo said to show the former planet was circulating on social media.

New Horizons captured this color-enhanced view of Pluto from a distance of 280,000 miles (450,000 kilometers) as it flew by the dwarf planet in 2015.

Pluto's 'almost twin' dwarf planet Eris has a rocky core blanketed by an icy shell, which appears to be flexing slowly.