It's the talk of the International Astronomical Union meeting, now underway in Prague. Astronomers are grappling over whether its small status should cause it to be declassifed as a planet.
Indeed, it's smaller than earth's moon and there are other objects past Neptune that are comparable in size to Pluto.
On the other hand, there are valid arguments to call Pluto a planet. It has an atmosphere, it goes through seasons, and it has three moons.
And what would happen to the mnemonic device for remembering planet names? You know: "My Very Educated Mother Just Served Us Nine Pizzas."
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