9 Reasons Kids Think Pluto Should Be A Planet Again — buzzfeed.com

The International Astronomical Union stripped Pluto of its planet status in 2006, because it only meets two of the three criteria in their new definition of a planet: A celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and © has cleared the neighbourhood around its orbit.

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