You can include Pluto if you wish to. There's things like Ceres and Make Make, but I haven't been able to find a complete, up-to-date list. The nature of the topic is rather hazy. Anyone care to shed light on our floating rocks?
My impression is that there are a lot. There are a few in the "asteroid belt". Ceres and Vesta come to mind, if I remember right. Then, a lot more outside of the orbits of the known planets. The recently demoted Pluto and its moon, come to mind, but I think there are many more, not all discovered and named, yet.
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