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The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

When the International Astronomical Union (IAU) demoted Pluto from a planet to a dwarf planet in 2006, it surprised a lot of ...

Charon is large in size relative to Pluto, and is locked in a tight orbit with the dwarf planet. A new simulation suggests how it ended up there. By Jonathan O’Callaghan Some 4.5 billion years ...

Discovered in 1930, Pluto was identified as the ninth planet until reclassified as a dwarf planet in 2006 following the landmark discovery of several similarly sized trans-Neptunian Objects or ...

As the gatekeepers to the Kuiper Belt, Charon and Pluto are a unique double dwarf planet system. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it ...

Charon is half the size of Pluto, “making it the largest known moon relative to its parent planet in our solar system,” NASA notes. So how did Pluto get its chonky companion? A new study ...