Planetary Classification

Planetary Classification is the process by which Starfleet categorizes the planets that are encountered. Features such as atmospheric composition, surface temperature, vegetation, and size are all essential components of the process of classifying a world.

Class	Description	Example
A	Geothermal world with hydrogen compounds in the atmosphere and inability to support life.	Gothos
B	Small, rocky worlds incapable of supporting life due to their proximity to the star.	Mercury
C	Small, rocky worlds incapable of supporting life due to their distance from the star.	Pluto
D	Moons or planetoids with little to no atmosphere that are unable to support life.	Luna
E	Planets featuring a poisonous atmosphere and a surface frequently covered with lava that are normally only capable of supporting carbon cycled life.	Excalbia
F	Geologically inactive and frequently lacking an atmosphere, these worlds are frequently high in resources and can, at times, support silicon based life.	Janus 6
G	Rich in both crystals and other minerals, these are small worlds that are normally uninhabited.	Delta Vega
H	Sparsely inhabited, these worlds are known for harsh conditions and are normally global deserts.	Tyree
I	These worlds are gas supergiants that reside in the cold zone of a star system.	Q'Tahl
J	These worlds are gas giants that reside in the cold zone of a star system.	Jupiter
K	Planets of this type feature a barren surface with little water and a thin atmosphere of carbon dioxide.	Mars
L	A class of barely habitable worlds known for their oxygen based atmosphere and lush vegetation, but have little to no animal life.	Indri VIII
M	The most habitable of all planetary types, these worlds feature an atmosphere that is highly supportive of maintaining life, abundant water, and extensive plant life.	Earth
N	Worlds belonging to this class have a high surface temperature due to the atmospheric greenhouse effect caused either naturally or by a global disaster.	Venus
O	Primarily oceanic, these planets feature aquatic based animal and plant life with little exposed surface land.	Betazed
P	Glaciated worlds featuring some vegetation and hardy animal life, these worlds typically experienced some form of global disaster.	Psi 2000
Q	Atypical planets that can feature diverse, tenuous climates all within the same surface region	Remus
R	Also known as a rogue planet, these worlds form outside of star systems - yet feature both animal and plant life and stable environments.	Dakala
S	These worlds are gas ultragiants that reside in the cold zone of a star system.
T	These worlds are gas ultragiants that reside in the cold zone of a star system.
U	These worlds are gas giants that reside in the cold zone of a star system.	Uranus
X	Planets of this type have been destroyed and are broken up into smaller pieces.	Genesis
Y	Also known as Demon Class, these planets are known for their toxic atmosphere, temperatures exceeding five hundred Kelvin, and heavy radiation.	Tholia

Real World

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