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[–] 4 points 13 hours ago (4 children)

The problem is that since Pluto was discovered, we've found many similar bodies. Astronomers suggest there could be hundreds.

If you define "planet" so that it excludes Pluto, 8 objects in our solar system qualify as planets. Any definition that includes Pluto qualifies at least 13 planets with a high likelihood that that number will increase every few years.

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  • [–] 1 point 2 hours ago* (last edited 1 hour ago) (3 children)

    It is convenient to classify it as a dwarf planet but that doesn’t mean that “dwarf planet” and “planet” are scientific categories in the purest sense of the term

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  • [–] 1 point 1 hour ago (2 children)

    What's the "purest sense of the term"? A planet is presently defined as a body which orbits a star, has enough mass to be roughly round, and has cleared its orbit of other objects. Dwarf planets are defined as fulfilling the first two criteria, but not the third.

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  • [–] 1 point 1 hour ago (1 child)

    I mean that these descriptions are somewhat arbitrary. Roughly round is not a very precise delineation, there will be edge cases where it’s not clear which category they fall into

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  • Roughly round is not a very precise delineation

    The actual qualification is "hydrostatic equilibrium", but I didn't want to complicate the point with technical mathematical jargon.

    there will be edge cases where it’s not clear which category they fall into

    Which is pretty par for the course so far as scientific classifications go. Classification is a human endeavor to attempt to neatly categorize things to better understand them, but the universe is what it is and defies tidy categorization. Just about any scientific classification you can devise will have edge cases and ambiguity.

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