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Memory Beta, non-canon Star Trek Wiki
Memory Beta, non-canon Star Trek Wiki
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A planet is a celestial body typically found in orbit around a star. Planets are typically spheroid and may have other bodies in orbit of themselves such as moons, rings or artificial satellites which can include communications or defense technology or orbital facilities 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. Still smaller bodies, which do not qualify to be named as planets, are asteroids.

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 (sharing meaning with 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")

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

Two partially conflicting listings of planetary classification have been given by the 1989 book The Worlds of the Federation and the 2002 book Star Charts. The two sources have classes D, K and M in common, but otherwise assign classifications to conflicting letters.

Star Charts classifications[]

Class Description Surface Atmosphere
Class A geothermal partially molten hydrogen compounds
Class B geomorteus partially molten, high temperature extremely tenuous, chemically inactive
Class C geoinactive low temperature partially frozen
Class D asteroid/moon barren and cratered metallic, iron-nickel-silicate 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 pressure and composition, may contain water vapor
Class J gas giant tenuous, comprised of gaseous hydrogen and hydrogen compounds, radiates some heat variable pressure 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 extremely dense, carbon dioxide and sulfides
class O pelagic 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 ultragiant tenuous, comprised of gaseous hydrogen and hydrogen compounds, radiates considerable heat variable pressure and composition, may contain water vapor
class T ultragiant tenuous, comprised of gaseous hydrogen and hydrogen compounds, radiates considerable heat variable pressure and composition, may contain water vapor
class Y demon 500K+ turbulent, saturated with toxic chemicals and therionic radiation

Worlds of the Federation classifications[]

Class Description Surface Atmosphere
Class A gas giant which radiates heat; a failed star tenuous if present reducing, including methane
Class B gas giant which does not radiate heat tenuous if present reducing
Class C high surface temperature iron/silicate dense reducing
Class D asteroid nickel-iron/silicate tenuous if present
Class E large molten core silicate, with some metals reducing/oxidizing
Class F less than a billion years old silicate, with some metals oxidizing
Class G desert silicate thin oxidizing
Class H geologically active silicate variable
Class I small and young metallic/silicate very dense fluid
Class J moon silicate tenuous, including noble gases
Class K adaptable with pressure domes silicate tenuous with some water
Class L geologically inactive silicate/water oxidizing
Class M geologically active silicate/water oxidizing
Class N pelagic entirely water oxidizing

Connections[]

multiverseuniversegalaxy
Galactic regions: quadrantsectorclusternebulastar system
System bodies: starplanetplanetoiddwarf planetmoonasteroidmeteoroidcomet

External links[]

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