Pluto's days, though they drag on a bit at around 153 hours, are nothing compared to its years. Pluto's orbit takes 248 Earth ...

Pluto sits far out in the Solar System, small and dim, moving at a pace that barely fits human timelines. It was found in ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. An illustration of confirmed dwarf planets and their moons. From left to right: Pluto (with ...

On August 24, 2006, the International Astronomical Union had decided on the official definition of a word that before that day had seemed almost unambiguous. They decided that a planet must meet three ...

Eighteen years ago today, Pluto lost its planetary status in a vote by International Astronomical Union (IAU) members on the final day of their 2006 general assembly meeting. The word "planet" comes ...

Using computer simulations, scientists based at NASA have pieced together the story of how the dwarf planet Haumea, found in the Kuiper Belt of icy worlds beyond the orbit of outermost planet Neptune, ...

The mystery of how Pluto got a giant heart-shaped feature on its surface has finally been solved by an international team of astrophysicists. The team is the first to successfully reproduce the ...