Moons are natural satellites. It's a ball shaped, smaller body that orbits around a larger body. The large mass of a planet makes a moon orbit around it. It's held in orbit by gravity. Natural bodies which orbit planets are called moons. Artificial bodies are manmade such as satellites. Some planets like Jupiter and Saturn have many moons.
Here's a list of notable moons in the Milky Way galaxy.
- Earth - 1 moon. The Moon
- Mars - 2 moons.
- Jupiter - 67 moons. Notable: Io, Europa, Ganymede, Callisto
- Saturn - 62 moons. Notable: Enceladus, Tethys, Dione, Rhea, Titan and Iapetus
- Uranus - 27 moons. Notable: Ariel, Umbriel, Titania and Oberon
- Neptune - 14 moons. Triton
- Pluto - 5 moons. Charon
- Haumea - 2 moons. Notable: Hi'iaka and Namaka
- 90482 Orcus - 1 moon. Vanth
- Mitterand Hollow - does a 360 degree orbit around its planet in just 1 minute and 26 seconds.