The Nature of Dwarf Planets

There's a lot of dwarf planets out there. That's one reason why Pluto isn't really a planet anymore because we discovered, mmm, it's kind of a lot of them out there. So I'm guessing that when we look at other solar systems, they've got the same thing going on. We expect that the same thing will happen to planets around other stars and to moons around those planets. Because of sort of the way that we can discover exoplanets, we expect a lot of the ones we've seen so far have been tidly locked.