• gandalf_der_12te@discuss.tchncs.de
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    5 days ago

    The current classification is a mess.

    IMO, it should be a planet iff it can hold an atmosphere. I.e., it doesn’t actually have to have an atmosphere, but if it had any, it should have enough surface gravity to hold that one.

    If you define it that way, Pluto is just barely a planet.

    • zqps@sh.itjust.works
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      5 days ago

      So whatever hypothetical density constitutes an atmosphere becomes the arbitrary line in the sand.

      • Spzi@lemm.ee
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        5 days ago

        Similar to the arbitrarily defined density of other stuff in the same orbit. We need to draw lines somewhere to impose categories on nature.

        • turmacar@lemmy.world
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          5 days ago

          Planet has never been very well delineated. The Sun was a “planet”. Ceres was a “planet”.

          When we find enough things to break up the classification, we make a new classification. Like “asteroid” or “dwarf planet” or “gas giant”.