How can astronomers determine the difference between “hydrostatic equilibruim” and “just happens to be spherical”?
This is relevant for the definition of a dwarf planet. I presume the answer will be, well, if we can tell the mass of the body and guess the material. I don't find this very satisfactory because ...
Related: Is there a upper limit to the number of planets orbiting a star? Can you explain the pattern of Hill sphere sizes of the objects of the Solar system? Could a habitable satellite of a gas ...