Planet is the common designation for a certain type of celestial body orbiting a star. They occur in a great variety of different compositions, masses and surface conditions. The exact definition of what constitutes a planet various among cultures.
Within the United Federation of Planets, celestial bodies with diameters below 100 km are usually classified as planetoids or asteroids rather than planets.
The final appearance of a planet depends on its formation process, which means where and under what circumstances it formed. Planets may accumulate gigantic atmospheres, exceeding their original size and mass, or they may rest without any atmosphere at all. With a sufficient mass, a planet is able to accumulate so much gas, that it starts to undergo nuclear fusion, turning into a protostar. In this state it begins to emit energy, as its core temperature and density increase. Planets can also be changed to a Class M environment by terraforming.
The Federation has numerous different classifications for planets depending on their mass, composition, surface environment and atmospheric compounds.
Types
Lists
All planets are collected on the list of planets. Additionally, several lists for specific groups of planets exist:
- Cardassian planets
- Dominion planets
- Earth colonies
- Federation colonies
- Federation members
- Homeworlds
- Inhabited planets
- Klingon planets
- Planets in the Delphic Expanse
- Romulan planets
- Uninhabited planets
- Unnamed planets