• shutz@lemmy.ca
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    5 months ago

    It’s not density, it’s mass. A mass of 1kg compressed to the density of the Sun’s core would pull the Earth with just as much force as a 1kg ball of styrofoam.

    • rockerface 🇺🇦@lemm.ee
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      5 months ago

      And is the Sun was replaced with a black hole of the same mass, the Earth would just keep on rotating around it without issues, if slightly frozen

      • chatokun@lemmy.dbzer0.com
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        5 months ago

        Xkcd did a what if on a black hole moon (getting it to collapse into one may be impossible, but a black hole the mass of the moon is theoretically stable), and it has the same conclusion, except just slightly colder instead of slightly frozen. And by slightly, I mean almost imperceptible.

        https://what-if.xkcd.com/129/

    • Chrobin@discuss.tchncs.de
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      5 months ago

      Just to add some formality to this, the original commenter might want to look up the shell theorem for classical mechanics and Birkhoff’s theorem for general relativity.