Planet Classification

Classifications

	Class A - Geothermal
	Class A geoactive planets are generally small, barren worlds rife with volcanic activity. This activity traps carbon dioxide in the atmosphere, causing a greenhouse effect that keeps the temperature very hot, regardless of the planet's distance from the sun. When the volcanic activity eventually ceases, the planet 'dies' and usually becomes a Class C world - a few rare cases transform into Class Q geothermal planets. Until that happens, the toxic levels of carbon dioxide make this planet unsuitable to any known life form, though silicon-based life may be able to terraform it to their needs.
	Age: 0 - 2 billion years Diameter: 1,000 - 10,000 km Location: Ecosphere/Cold Zone Surface: Partially molten Atmosphere: Primarily hydrogen compounds Evolution: Cools to become Class C Life Forms: None Example: Gothos
File:D-Class.png	Class B - Ferromorteus
	Class B planets are small, mostly metallic rocky planetoids. Class B worlds exhibit a highly iron-rich crust, with a magnetic core and no mantle. Atmosphere thin to negligible, with little to no heat retention. The surface varies from extremely hot to cold dependent on the position relative to their star, and can exhibit molten surface areas. The night side of the planetoid will fail to retain the heat exhibited on the day side, left a frigid wasteland. These planetoids are inimical to life.
	Age: 0 - 10 billion years Diameter: 1,000 - 10,000 km Location: Hot Zone Surface: Partially molten, high surface temperatures Atmosphere: Extremely tenuous, few chemically active gasses Life Forms: None Example: Mercury
File:D-Class.png	Class C - Geoinactive
	When all activity on a Class A world ceases, the planet is then considered Class C. Essentially dead, these small, rocky worlds have a cold, barren surface. As their core cooled down, their rotation slowed and eventually their atmosphere dissipated. No life form as any use for these planets, although they do often possess rich mineral deposits from their volcanically-active past.
	Age: 2 - 10 billion years Diameter: 1,000 - 10,000 km Location: Ecosphere/Cold Zone Surface: Low surface temperature Atmosphere: Frozen Life Forms: None Example: Psi 2000
File:D-Class.png	Class D - Asteroidal Dwarfs
	D class planets are most commonly found in the Ecosphere of a system but are not strictly limited to - they are found as well in the Hot and Cold Zones - they range between 5 to 10 thousand kilometres in diameter. They are barren and rocky, often possessing no atmosphere. Animal life is unable to form on D class planets. Depending on their proximity to a star, a D class may be hot and arid or cold and frozen. These planets can be made habitable by terraforming as was the case with Weytahn by the Andorians during the 2050s.
	Age: 2 - 10 billion years Diameter: 100 - 1,000 km Location: Hot Zone/Ecosphere/Cold Zone; found primarily in orbit of larger planets or in asteroid fields/belts Surface: Barren and cratered Atmosphere: None or very tenuous Life Forms: None Example: Luna, Ceres
File:D-Class.png	Class F - Icy Dwarfs
	Class F dwarf planets are planetary-mass objects found in the outer areas of a planetary system that are devoid of complex lifeforms, with a rocky crust covered in nitrogen ice, and an atmosphere tenuous in the extreme. Class F worlds are incapable of retaining the limited heat they receive from their distant parent star. There may, however, be subsurface water, heated by mantle activity, which can provide the basis for colonisation through pressure domes.
	Age: 0 - 10 billion years Diameter: 100 - 1,000 km Location: Cold Zone Surface: Covered in ice Atmosphere: None or very tenuous Life Forms: Rare; microbial Example: Pluto
File:H-Class.png	H Class 'Desert'
	H class worlds are found in the Ecosphere of a system and range between 5 to 15 thousand kilometres in diameter. Their atmospheres may be rich in oxygen, carbon dioxide, or another common gas. The planet holds little to no surface water; the entire world a sea of dunes and sand and is sustained to be very dry, hot, and barren. Little life is known to inhabit these worlds. They are inhabitable by either pressure domes or colonies, depending on the atmospheric content, through supply replenishment; use of aquifiers is necessary. Example: Tau Cygna V
File:J-Class.png	J Class 'Gas Giant'
	Typically located in a system's Cold Zone, J classes are uninhabitable. Also known as Gas Giants due to their general lack of a solid surface, their dense atmospheres are most commonly made of gases such as ammonia, ethane, fluorine, helium, hydrogen, and methane. Windspeeds average 2000 kilometres per hour, however the USS Defiant in 2372 recorded windspeeds of 10 thousand kilometres per hour on an unnamed J class when rescuing a Karemma vessel. The diameter of a J class ranges between 50 and 140 thousand kilometres, therefore they possess a very strong gravitational pull which results in dozens to hundreds of planetoid moons in their orbits. Rings made up of spacial debris caused by lunar collisions and the collection of space dust and ice are common. As observed by the USS Enterprise-D in 2369, the collision of two J class planets can ignite the birth of a star. A single J class does not have sufficient resources or energy to cause fission resulting the creation of a star, however when two collide their combined resources is enough to do so. Examples: Jupiter, Saturn, Betelgeuse III
File:6-Class.png	Class 6 'Ice Giant'
	Similar to a J class, the Class 6 is distinctly different in that is has a global ocean composed of liquid gases beneath its layered atmosphere. These oceans are known to be made of water-ammonia and hydrogen-methane. Examples: Uranus, Neptune
File:K-Class.png	K Class 'Adaptable'
	K class planets are located within the Ecosphere of a system and range 5 to 15 thousand kilometres in diameter. They have very thin atmospheres usually composed of carbon dioxide, nitrogen, and/or argon. Their weak magnetic fields allow large quantities of solar radiation to reach the surface and heat to escape back into space. K class surfaces are barren, often cold, and cannot support animal life as there is commonly no liquid water or too little to sustain vegetation. Colonisation is possible by the use of pressure domes. Examples: Mars, Mudd
File:L-Class.png	L Class 'Marginal'
	L class planets are located within the Ecosphere of a system and range between 10 to 15 thousand kilometres in diameter. The atmosphere is mostly made up of oxygen and argon but also has a very high concentration of carbon dioxide. Unlike the M class, the L class has little water and vegetation, but it could thrive if conditions were set properly. Life tends to be predominantly plant life with few animals. Most L classes are suitable for humanoid colonisation. Example: Indri III
File:M-Class.png	M Class 'Terrestrial'
	M class planets are located within the Habitable Zone of a system and range between 10 to 15 thousand kilometres in diameter; they are the rarest class of planet. Their atmospheres are rich in nitrogen and oxygen. Water and animal lifeforms are very common due to an overabundance of marine and surface vegetation which thrive on the planet's temperate climate. M class planets are home to the vast majority of sentient and technologically advanced species, especially humanoids. At least 75% of the planet is covered in liquid water. Examples: Earth, Vulcan, Romulus, Cardassia Prime, Bajor, Qo'Nos
File:N-Class.png	N Class 'Reducing'
	N class planets are located within the Ecosphere of a system and range 5 to 15 thousand kilometres in diameter. They have very thick, dense, atmospheres carbon dioxide as well as sulfides that stage an irreversible and constantly worsening greenhouse effect. This causes an extremely high surface temperature that enables water to exist only in the form of vapour. Abundant volcanism is very common. Animal life is unable to exist and colonization is not possible. Examples: Venus
File:P-Class.png	P Class 'Glaciated'
	P class planets are found in the Ecosphere of a system and range between 10 to 15 thousand kilometres in diameter. A planet falls under this classification when its surface is 80%+ water ice and its atmosphere mainly consists of nitrogen and oxygen. Animal and humanoid life forms are usually common and so is rugged tundra-like vegetation. Examples: Andor, Exo III
File:T-Class.png	T Class 'Super/Ultra Giant'
	The T class Super or Ultra Giant is a Gas Giant on the verge of becoming a star. It may also be the immediate result of two colliding J class planets if star birth does not immediately occur thereafter. These planets are hot enough to appear to be molten or burning and produce their own dim light. Moons orbiting this planet may become globules of liquid if once frozen or may singe their atmospheres. These extreme heats, however, only occur in the final stages of a Super Giant's. Before becoming a star it is also known as a Brown Dwarf. The Super Giant is the largest of all known planetary classes, homing in with a diameter anywhere between 350 to 700 thousand kilometres. In 2375, the USS Voyager encountered a Super Giant in the Delta Quadrant that had radiogenic rings.
File:Y-Class.png	Y Class 'Demon'
	Y class planets can be found anywhere within a system and they range between 10 to 15 thousand kilometres in diameter. A planet is classified as a Demon when their atmospheres are toxic, temperatures are above 500 Kelvin, and they give off bursts of thermionic radiation. Entering orbit of a Y class planet can be harmful to crew and ship alike. In 2374, the USS Voyager was forced to land on a Y class planet on its return voyage from the Delta Quadrant to retrieve desperately needed deuterium. It was discovered that the deuterium was inside a bio mimetic lifeform called 'Silver Blood' which created a duplicate of Voyager and its crew. The duplicate was ultimately destroyed a year later in 2375.
	Z Class 'Tachyon'
	The class Z planet is a rare, and until recently, completely unknown phenomena. Z class planet's are unique for their tachyon core's which cause them to rotate indifferently than the rest of the planet's in the galaxy. This causes a huge differential in fabric of space time which causes time on the planet to pass immensely more quickly, or in one case, much slower than the rest of the universe. This type of planet was first encountered by the Federation in 2374 dangerously close to the galactic core. The USS Voyager also encountered a similar planet in the Delta Quadrant in 2376 during it's return journey home. Two other planet's are known to exist. All distribute very similar properties, with only the one encountered by Voyager being inhabited, and one of the planet's displacing time much slower than the rest of the universe. The largely unknown, unique, and somewhat unpredictable properties of these type of planets make them nearly impossible to properly explore and investigate without causing the loss of a starship. With the exception of Voyager, all research on these type of planets have been done from afar which causes the data to be incomplete. On large, the known planets of this type are avoided by all who are aware of it's properties.

Planetary Zone Classification Map

Planetary Zone Classifications Map

Credits

Descriptions, Icons, and Map created by and used with permission from Schmidt. Information originally created/gathered for the USS Fitzgerald, Star Trek Roleplaying Game. Information concerning granting of permission can be obtained via your CO or TFCO. Should specific topic be archived, please contact the Administrator.