In the time Pluto was found, classified as a planet and reclassified as a dwarf planet, it has not completed one orbit. One year on the distant ice planet is 248 Earth years, and one day is 153 Earth ...

In 1930, scientists discovered a small celestial body on the outer edge of our solar system. They called it Pluto and classified it as a planet. However, the International Astronomical Union (IAU) — ...

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 ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. This image of Pluto was made after the New Horizons spacecraft flew past the dwarf planet on July ...

Before Pluto was discovered, it was predicted. Astronomers had observed that massive objects can affect the orbits of their neighbors and, after seeing deviations in the orbits of Uranus and Neptune, ...