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unangbangkay
!f3zMLtBTIk
>>306808 Actually, the term is "Pluton". So is Charon and 2003UB313, informally known as "Xena". A Pluton is post-Neptune orbiting planet with an eccentric (non-circular) orbit path.
Pluto is still very much a real planet, but the need to actually, physically define planets was real. And there was no way to come up with any meaningful definition of a planet and still have only 9 of them.
So Astronomers went with gravity as the main determinant, specifically gravity strong enough to pull it into a circular shape while still orbiting the star (and not another planet).
As for Charon, Pluto and Charon will be a dual-pluton system, since they orbit each other.
Ceres will also be a planet.
There are at least 12 MORE candidates that will be evaluated for classification over time.
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