57 Comparing Planets
We will look at our Solar System and its worlds from a comparison perspective, called Comparative Planetology , rather than focus on a lot of numbers and data. To compare the planets, they will be grouped into two major types: the Rocky or Terrestrial (Earth-Like) planets , and the Gas Giants or Jovian (Jupiter-like) planets . Recall, the focus of this module will be on the Rocky Planets. The next module will focus on the Gas Giants.
The table, Rocky Planets Vs. Gas Giant Planets , provides a broad snapshot of the differences between the Rocky Planets and the Gas Giant Planets.
Rocky Planets Vs. Gas Giant Planets
Rocky Planets: Mercury-Venus-Earth-Mars
Characteristics:
- Distance from the Sun — Close
- Revolution Length — Short
- Surface Type — Solid surface
- Diameter — Small
- Craters — Many
- Water — All except Venus
- Rings — None
- Satellites — Few or none
Gas Giant Planets: Jupiter-Saturn-Uranus-Neptune
Characteristics:
- Distance from the Sun — Farther out
- Revolution Length — Long
- Surface Type — Gas; Probably no surface or very small icy core
- Diameter — Large
- Craters — None (gas)
- Water — Yes; in the atmosphere (gas)
- Rings — Yes; from one to multiple rings
- Satellites — Many
