Pluto isn't alone—it's part of the Kuiper Belt with possibly hundreds of other planet-sized objects. Because Pluto hasn't ...

Once the quirky underdog of our solar system, Pluto held planetary status until 2006, when it got a cosmic demotion that still stings space fans. Discovered in 1930, Pluto was the ninth planet for ...

The controversy endures over Pluto's true status, but the solar system underdog continues to capture hearts across the globe. When you purchase through links on our site, we may earn an affiliate ...

Pluto was discovered at Lowell Observatory in Flagstaff, Arizona in 1930 and was considered our ninth planet until 2006. The International Astronomical Union reclassified Pluto as a dwarf planet ...

(Correction: An earlier version of this story misstated how far Pluto is from the sun. The correct number is 3.7 billion miles.) What was discovered in Flagstaff, Arizona, and killed off in Prague? If ...

Pluto is a bit of a loner. The dwarf planet is no longer considered a regular planet; it does not orbit on the same plane as the solar system's eight planets; and its orbit is both highly elliptical ...