Planet

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A planet is a celestial body typically found in orbit around a star. Planets are typically sphereoid and may have other bodies in orbit of themselves such as moons, rings or artifical satalites which can include communications or defence technology or orbital facilites such as starbases and shipyards. There are two basic types of planets, small solid rocky planets which may have a thin atmosphere and gas giants which are almost entirely atmosphere. Small planet like bodies are planetoids or dwarf planets and smaller bodies still are asteroids.

[edit] Planetary Classification

The Federation classified planets it cataloged based on criteria such as atmospheric composition, surface temperature and conditions, the size of the body and the presence of animal and plant life. This system is used to determine the suitability of the planet for exploration, colonization and scientific research.

Each class of planet is assigned a letter in the alphabet based on its suitability. For example, Class M (based on the Vulcan designation Minshara-class) is applied to planets that can support life without any special circumstances, such as Earth, Vulcan or Cardassia. (ST reference: Star Charts; ENT episode: "Strange New World")

Class	Description	Surface	Atmosphere
Class A	Geothermal	Partially molten	Hydrogen compounds
Class B	Geomorteus	Partially molten, high temperature	Extremely tenuous
Class C	Geoinactive	Low temperature	Frozen
Class D	Asteroid/Moon	Barren and cratered	None or very tenuous
Class E	Geoplastic	Molten, high temperature	Hydrogen compounds and reactive gases
Class F	Geometallic	Volcanic	Hydrogen compounds
Class G	Geocrystalline	Crystallizing	Carbon dioxide, some toxic gases
Class H	Desert	Hot and arid, little or no water	May contain heavy gases and metal vapors
Class I	Gas Supergiant	Tenuous, comprised of gaseous hydrogen and hydrogen compounds, radiates heat	Variable presure and composition, may contain water vapor
Class J	Gas Giant	Tenuous, comprised of gaseous hydrogen and hydrogen compounds, radiates some heat	Variable presure and composition
Class K	Adaptable	Barren, little or no water	Thin, mostly carbon dioxide
Class L	Marginal	Rocky and barren, little water	Oxygen/Argon, high concentration of carbon dioxide
Class M	Terrestrial	Water abundant	Nitrogen, Oxygen and trace elements
Class N	Reducing	High temperature	Extreamly dense, carbon dioxide and sulfides
Class O	Palagic	80%+ water	Nitrogen, Oxygen and trace elements
Class P	Glaciated	80%+ water ice	Nitrogen, Oxygen and trace elements
Class Q	Variable	Various	Tenuous to dense
Class R	Rogue	Maybe temperate due to geothermal venting	Primarily volcanic outgassing
Class S-T	Ultragiant	Tenuous, comprised of gaseous hydrogen and hydrogen compounds, radiates considerable heat	Variable presure and composition, may contain water vapor
Class Y	Demon	500°K+	Turbulent, saturated with toxic chemicals and therionic readiation

The Klingons had a separate classification system, one of which is a Q'tahL class. (ENT episode: "Sleeping Dogs")

[edit] Connections

• For a list of planets see Planets or Planets and planetoids.
• Planet article at Memory Alpha, the wiki for canon Star Trek.

Multiverse • Universe • Galaxy
Galactic Regions:	Quadrant • Sector • Cluster • Nebula • Star system
System Bodies:	Star • Planet • Planetoid • Dwarf planet • Asteroid • Meteoroid • Comet