The new rules say a planet must be “a celestial body that is in orbit around the sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a … nearly round shape, and has cleared the neighborhood around its orbit.” Pluto doesn’t make the cut since its orbit overlaps with Neptune’s.
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Watch a video: Pluto—Does Size Matter?
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The astronomers have voted. Now what do you think about Pluto’s demotion?
Image of Pluto and its moon Charon courtesy NASA