The Solar System is the gravitationally bound system of the Sun and the objects that orbit it. There are numerous small solar system bodies that orbit around the Sun, but most recognizable are the 8 planets of the Solar System, which include (in order from distance from the Sun): Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Some would also include the dwarf planet Pluto among this list, which was once considered a planet, but was laid off by NASA in 2006.
These planets can be divided into two regions: the Inner Solar System and the Outer Solar System. There is a considerable distance between any planets between the inner and outer solar system, which easily separates them into their own categories.
Inner Solar System
The Inner Solar System is known for containing the first four planets of the Solar System, known as terrestrial or rocky planets. These of course include Mercury, Venus, Earth and Mars. The asteroid belt is also here, and exists in the regions between the Inner and Outer Solar System.
Outer Solar System
The Outer Solar System contains gas giants and icy planets, which include Jupiter, Saturn, Uranus and Neptune. These planets are all much larger than the terrestrial planets and have much greater distance between each planet; the distance between Jupiter and Saturn alone is larger than the Inner-Solar System.
The Trans-Neptunian Region is everything in the Solar System that exists beyond the planet Neptune. The Kuiper belt resides in this region, which is similar to the Asteroid belt, except primarily consists of ice instead of rock and is 20 times as wide and 20–200 times as massive. Pluto is the largest known object in the Kuiper belt. Various other dwarf planets also exist in the Trans-Neptunian Region.
- Solar System
- Solar System model
- Outline of the Solar System
- List of Solar System objects
- List of Solar System objects most distant from the Sun
- List of Solar System objects by size
- List of gravitationally rounded objects of the Solar System
- Formation and evolution of the Solar System
- Discovery and exploration of the Solar System
- Timeline of discovery of Solar System planets and their moons
- Timeline of Solar System exploration
- Timeline of Solar System astronomy
- Lists of geological features of the Solar System
- List of Solar System extremes
- Solar System in fiction