I would like to propose definitions, for others to modify / improve: (1) Satellites have at least part of their orbit about the sun convex toward the sun and go around one moon or planet, when view from that moon or planet. (2) Asteroids are no bigger than seda or pluto (which ever is bigger or any similar mass yet slightly bigger found later) and have eveywhere concave to the sun orbits. They divide into two subgroups, spherical and non spherical. (3) Comets have orbits concave to the sun and approach it close enough to change shape when near the sun. (4) Moons have all of their orbit about the sun concave towards the sun and are too small to be considered planets, but stay relatively close to a planet. (5)Planets have the mass of Mercury or greater and orbits every where concave towards the sun. Solar system has 8, four are "gas giants" and four are terrestrial.
