Here is an image, to proper sizing, of all the round bodies in the solar system that we have images of with an interesting data point: they are not planets. These are the moons and "dwarf planets" from our moon to Vesta and Ceres, the Jovian moons, all the way out to Pluto.
All this solid ground, waiting to be walked on, explored and colonized. And I was born too early to watch it happen.