What about the other dwarf planets in our solar system? Ceres, Eris, Makemake and Haumea are in the same size range as Pluto. Also, many of Jupiter and Saturn's moons are larger than Pluto, including Ganymede, Titan, Callisto, Io, Europa and Triton. Even Earth's own moon is bigger than Pluto. Charon, the largest moon of Pluto comes in at about half its size even.
It's difficult to define things properly based on just size alone. Personally I think they all should be classified as planets if they are above the Roche radius where the material they are made of can coalesce into a solid mass and become spherical due to their own gravity shaping them that way. Even if they orbit another planet, they should be planets not moons, IMHO.
What about the other dwarf planets in our solar system? Ceres, Eris, Makemake and Haumea are in the same size range as Pluto. Also, many of Jupiter and Saturn's moons are larger than Pluto, including Ganymede, Titan, Callisto, Io, Europa and Triton. Even Earth's own moon is bigger than Pluto. Charon, the largest moon of Pluto comes in at about half its size even.
It's difficult to define things properly based on just size alone. Personally I think they all should be classified as planets if they are above the Roche radius where the material they are made of can coalesce into a solid mass and become spherical due to their own gravity shaping them that way. Even if they orbit another planet, they should be planets not moons, IMHO.
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