A planet is taught to us (at primary school) as a ball of rock that orbits around the Sun and is similar to our own planet, Earth (in as a ball of rock). But of course, humans have to be more specific than that so there must be some internationally agreed on requirements to define a planet by an official committee, right? I know of an example of this is when in 2006, these requirements were enforced and Pluto got demoted from planet status to dwarf planet status.



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