Rocky Moons:
* Most common type: Many moons, especially smaller ones, are primarily composed of rock.
* Examples: Our own Moon, Mars's moons Phobos and Deimos, Jupiter's moons Io and Europa, Saturn's moon Mimas.
* Characteristics: Have a solid surface, often with craters, mountains, and valleys.
Gassy Moons:
* Less common: Only a few moons are primarily composed of gas.
* Examples: Saturn's moon Titan, which has a dense atmosphere composed mainly of nitrogen.
* Characteristics: Have an atmosphere, often with clouds and weather patterns.
Mixed Composition:
* Many moons have a combination of rock and ice: This ice can be water ice, ammonia ice, or other frozen compounds.
* Examples: Jupiter's moons Ganymede, Callisto, and Europa are primarily composed of rock and ice.
In summary: The composition of a moon depends on its formation process and its distance from its host planet. Rocky moons are more common, but some moons are gassy or have a combination of rock and ice.
