It would probably be based on a homesteading system. In the case of a planet, you'd get what you changed. In the case of an asteroid, if you moved it into a dif

It would probably be based on a homesteading system. In the case of a planet, you'd get what you changed. In the case of an asteroid, if you moved it into a different orbit and set up facilities on it that's probably enough to count as a homestead.