• AVincentInSpace@pawb.socialEnglish
    17·
    1 year ago

    it always kinda bugs me that people lose their minds over Pluto but can’t name even one of the other four dwarf planets in our solar system

      • Pegajace@lemmy.worldEnglish
        312·
        1 year ago

        No, because absolute size is not what makes a moon a moon. Our Moon is a moon because it directly orbits a planet, not a star. Charon is massive enough relative to Pluto that the former does not directly orbit the latter, but instead they both orbit a common barycenter located between them, making them a binary planetary system.

          • Pegajace@lemmy.worldEnglish
            1·
            1 year ago

            Not quite. All two-body systems orbit a common barycenter, but the mass ratio of the Earth-Moon system is so lopsided that the barycenter is inside the Earth, not between them like with Pluto and Charon.

      • Zellith@kbin.social
        5·
        1 year ago

        The barycenter between earth and the moon is within the earths crust. The barycenter between charon and pluto is outside of plutos surface. For those who dont understand, this means that the center of gravity between the earth and moon is INSIDE the earth. So the moon orbits a point within the earth. Not so with the charon pluto system. Both worlds orbit a point in space.

        If the moon was to have its own orbital path around the sun, then sure. It would be a planet imo. It’s rounded by its own gravity… and it would orbit the sun.

        But I guess if we want to the meat of the subject about what defines a planet in the most basic sense, it would be things that make Earth a planet, since we pretty much all agree Earth is a planet. So… rounded… Orbits the sun… What else would you say describes the Earth?