Groups of planets refer to a collection of celestial bodies that orbit the same star or exist within a specific region of a celestial system. In our own solar system, these groups are primarily categorized based on their proximity to the Sun or their location in the solar system.
The most prominent group of planets in our solar system is the inner planets, also known as the terrestrial planets, consisting of Mercury, Venus, Earth, and Mars. These planets are characterized by their relatively smaller size, solid surfaces, and proximity to the Sun. They are predominantly composed of rocky material and exhibit distinct features such as mountains, valleys, and impact craters.
The outer planets, on the other hand, constitute the second significant group. Also referred to as gas giants or Jovian planets, they include Jupiter, Saturn, Uranus, and Neptune. These planets are mostly composed of gases and lack a solid surface. They are significantly larger and more massive than the inner planets, with their atmospheres being predominantly composed of hydrogen and helium.
In addition to the inner and outer planets, there are other groups within our solar system, such as dwarf planets like Pluto and Eris, which are small celestial bodies that did not clear their orbital path and reside in the Kuiper Belt. Asteroids and comets are other groups of celestial objects that exist in different regions of the solar system beyond the planets.
Beyond our solar system, groups of planets may also exist in other star systems. Termed exoplanetary systems, these groups comprise planets orbiting stars outside of our sun. They can range from single-planet systems to more complex multi-planet systems, mirroring the diverse arrangements found within our own solar system.
