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Big, spheroid but no Planet
Take a look at this nice montage of "Not-Planets" made by
And while they all pretty much look like planets they don’t meet the criteria for planets set by the International Astronomical Union (IAU). Basically planets have to be massive enough to be rounded by their own gravity but not massive enough to undergo thermonuclear fusion and also must have cleared their orbits from planetesimals (more or less big chunks of rock). And of course a planet can’t be a moon of another object.
And if you are still sad about the reclassification of Pluto bear in mind that a rose by any other name would smell as sweet…
More on planets:
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