Dwarf planet Hygiea within the asteroid belt also has no moon. On the other hand, a number of more compact asteroids (also known as minimal planets) do have moons, but they are all also faint to discover in almost any amateur telescope. Phobos is with a collision class with Mars. https://bestmoons72603.activablog.com/33821473/5-tips-about-best-moons-you-can-use-today