Planetary Classifications

Class (Vulcan Name)	Description	Surface	Atmosphere	Image
Class A (Ayhan) (ex: Io, Gothos)	Geothermal Class A planets are small, normally less than 3,200 km in diameter and extremely geologically unstable. Because of this they tend to be quite young planets, normally only in their first billion years of existence. Due to volcanic activity they have high amounts of carbon dioxide in their atmosphere that keeps them extremely hot. When this activity stops the planets tend to become Class C planets. Even protected surface missions are not advised; there is no natural life of any sort. Uninhabitable	Partially molten	Trace (hydrogen compounds)
Class B (Balev) (ex: Mercury)	Geomorteus Class B planets are small, normally less than 3,200 km in diameter and highly unsuited for humanoid life. They are normally quite close to the system's core with thin atmospheres of helium and sodium. Due to this make-up and the close distance to the sun or suns, they have mostly molten surfaces. During daylight, because of the thin atmosphere it can reach over five hundred degrees Kelvin, at night it can get as low as 73 Kelvin. With these extremes, life has never been known to evolve on these planets, however they have been known to occasionally have bacterial life on their surface from comet impacts. Uninhabitable in all but a few rare cases	Partially molten, high temperature	None or trace
Class C (Chu’lak)	Geoinactive Almost all Class C planets start their lives as Class A planets and change once they stop being geologically active. Losing the atmosphere they had, they become completely barren, just a rock in space. Being more stable than Class A, they can be colonized with pressure domes and mined for resources. They are still normally less than 3,200 km in diameter and have limited gravity. Inhabitable when pressurized	Low temperature	Frozen
Class D (Denak) (ex: Luna, Pluto)	Dwarf Planet Class D or dwarf planets are usually small worlds, only about one thousand to 3,200 kilometers in diameter. These worlds are typically dominated by craters, but are otherwise barren. Dwarf planets are relatively old, between two to ten billion years old. Class D objects are composed primarily of rock and ice, however their composition is heavily dependent on the location within the system. Objects in this class can exist within any region of a star system, between the hot zone to the cold zone. Because of their low mass, some dwarfs have very tenuous atmospheres, while many completely lack one. Although not unheard of, Class D objects rarely possess life and are unsuitable for humanoid life, the environment can be adapted with pressure domes. Often, Class D objects are moons of other planets, comets, dwarf planets or very large asteroids. Inhabitable when pressurized	Barren and cratered	None or trace
Class E (Evoras) (ex: Excalbia)	Geoplastic Class E planets are the first stage of the development of a habitable planet. From core to crust they are molten but cooling. They can have a range of atmosphere but tend to have high levels of carbon dioxides, hydrogen and helium. Being larger than a Class B at between 3,200 and 10,000 kms, they are more able to retain their atmosphere, while still having very high temperatures and being hazardous to almost all forms of life. If the planet is in the temperate zone and starts to cool to the extent they develop a crust, they become a Class F planet; if not in the temperate zone, they transition into a Class N planet. Uninhabitable	Molten, high temperature	Varied: trace, thin, standard or thick (hydrogen compounds and reactive gases)
Class F (Falor) (ex: Janus IV)	Geometallic Class F are planets at the most basic start of life. As volcanic activity starts to cool down and the crust solidifies, if a fluid medium such as water can form, life can as well. While still active and hostile to most humanoid life due to high levels of carbon dioxide and unstable surface temperatures, for a few minutes the air can be breathable. This class will normally only form in a system's temperate zone; if they are in the hot zone, they remain Class E for the rest of their existence. As the planet cools further and becomes volcanically stable, they transition to Class G. Uninhabitable	Volcanic	Varied: thin, standard or thick (hydrogen compounds)
Class G (Galsh) (ex: Delta Vega)	Geocrystalline Class G planets are habitable. While volcanic activity is still sporadic, the cooler and older planet is able to sustain complex life. Algae and mosses start to form, along with soft animal life such as jellyfish. Oxygen is in abundance along with nitrogen and, while there wouldn't be food for them, humanoids can survive on these worlds indefinitely. They are rocky with developing oceans and seas but are silent worlds. Depending on state and position of the planet, a Class G can become a Class H, K, L, M, N, O or P world. Inhabitable	Crystallizing	Varied: thin, standard or thick (carbon dioxide, some toxic gases)
Class H (Harauk) (ex: Vulcan)	Desert A Class H planet is almost entirely desert; at most they have only 20% of their surface covered in water. Young planets of four to six billion years old tend to be rocky, while those that are older tend to be covered in sand. Life can evolve here but it is limited, plants tend to be small, as do animals. Weather tends to be dry, with sandstorms and still days with few clouds. Some have snow on their poles and can experience wider variations of weather. They are often incapable of naturally supporting populations above a hundred million humanoid lifeforms. Inhabitable	Hot and arid, little or no water	Varied: thin or standard (may contain heavy gases and metal vapors)
Class I (Ivek) (ex: Uranus, Neptune)	Ice giant Class I planets are completely different from smaller molten core planets; their cores are mostly made of rock and ice. Layers of water, methane and ammonia make up the rest of the planetary body. They are large planets, between 10,500 and 55,000 kms radius, and tend to only form on the fringe of a solar system. They also tend to have very strong magnetic fields at each rotational pole. Uninhabitable	Cores are mostly made of rock and ice	Layers of water, methane and ammonia
Class J (Jasif-ir) (ex: Jupiter, Saturn)	Gas Giant If Class I are 'large' planets, Class J are 'giants'. At between 55,000 and 900,000 kms radius, even the largest is quite far from the verge of becoming dwarf stars. Made up of liquid and gaseous hydrogen, their cores even made up of hydrogen compounds. Winds of over 600 kph lick the surface during storms making them extremely hazardous. Due to their size and gravitational pull, they often can form rings of matter that fall into their orbit. Forming in the medium to outer areas of a solar system, they tend to be closer to the star than a Class I planet. Uninhabitable	Comprised of gaseous hydrogen and hydrogen compounds; radiates some heat	Variable pressure and composition
Class K (Kesh) (ex: Mars)	Adaptable Class K planets are much like their Class H counterparts, but the atmosphere is too weak. Only capable of supporting single cell life they aren't very habitable and fluctuations in temperature would kill most humanoids over a few days. They can, however, be colonized with pressurized domes. Inhabitable when pressurized	Barren, little or no water	Thin (mostly carbon dioxide)
Class L (L’Nel)	Marginal Class L worlds are young planets that haven't yet developed animal life. They tend to be covered in forests and plants that are broken down by simple organisms and fungi. Water is not common and those with less than 20% surface coverage fall to being Class H. These planets, however, are perfect for colonization and terraforming. Impact of native life is minimal and minimum effort is needed. Inhabitable	Rocky and barren, little water	Varied: thin, standard or thick (oxygen/argon, high concentration of carbon dioxide)
Class M (Minshara) (ex: Earth)	Terrestrial Class M planets are perfect for most humanoids, they are stable and can often evolve humanoid and other complex animal life. The land masses are mostly rocky but covered in soil and vegetation, twenty to eighty percent of the planet is covered in water. The only other requirement is that it must have a breathable oxygen-nitrogen atmosphere and a temperate climate. Most species in the known universe originated from planets of this class. They are found in the ecosphere of a star that allows their development. Inhabitable	Water abundant	Varied: thin, standard or thick (nitrogen, oxygen and trace elements)
Class N (Nesheh) (ex: Venus)	Reducing Class N1 planets are failures when compared to Class M. While they may appear in a similar location in a star's ecosphere, they are barely hospitable for any race. They are barren with temperatures that reach over 700 Kelvin. Massive amounts of carbon dioxide cover the surface and build up a pressure a hundred times that of an M Class world. This means that from space, it seems like the planet is entirely covered in clouds. Uninhabitable While Class N1 planets are among the hottest planets known to exist, at the opposite end of the temperature spectrum is the frigid Class N2. Though similar in appearance to N1 thanks in part to the dense atmosphere and characteristic veil of thick clouds, this secondary class is structurally very different. Temperatures are so cold that liquid methane can pool into lakes, and vast mountain ranges are made of rock-hard ice. Uninhabitable	High temperature (N1) Low temperature (N2)	Extremely dense (carbon dioxide and sulfides)
Class O (Ob'taree)	Pelagic Class O planets are covered in water; to qualify, a planet needs to be more than 80% surface water. Due to the water they absorb and store, a lot of the heat still reaches the planet, making the atmosphere very charged. They can support vast aquatic ecosystems, as well as tropical islands on peaks above the water. These planets tend to have the most living matter compared to others and teem with vast variations of species. While most do not evolve humanoid life, some do (though they are normally aquatic). Inhabitable	80%+ water	Varied: thin, standard or thick (nitrogen, oxygen and trace elements)
Class P (Paradaik) (ex: Andor, Breen)	Glaciated On the distant edge of a star system's ecosphere, habitable planets are still numerous, but they are a far cry from the lush garden worlds closer in. Cold and barren, more than eighty percent of a glaciated planet is covered in solid ice, and while many possess narrow stripes of green along the equator, where hearty plant and animal life may flourish, many glaciated worlds are entirely frozen. Despite the harsh conditions, humanoid life can thrive on a glaciated world. Inhabitable	80%+ water ice	Varied: standard or thick (nitrogen, oxygen and trace elements)	File:Class P.png
Class Q (Qju'nirr) (ex: Genesis Planet)	Variable Class Q planets are rare occurrences that, due to unstable orbits or variable stars, constantly change what their surface conditions are like. Due to its orbit, the surface can both freeze and boil, be suitable for life and be hostile. Some extremes are less pronounced and dabble between different ecospheres, such as deserts of a few miles next to tiny rainforests and swamps. This eclectic mix is more often caused by multiple stars in a system, unlike the more widespread extremes resulting from orbit oddities. Though pockets of the surface might occasionally become habitable, in general, the constant instability makes long term survival for any species virtually impossible.Often completely uninhabitable, but inhabitable regions may exist	Various	Varied: trace to dense
Class R (Ri'a'gra)	Rogue A rogue planet usually forms within a star system, but at some point during its evolution, the planet is ejected from a stable orbit and expelled into interstellar space. Typically, this is caused by a catastrophic asteroid impact or interaction with a wandering Class T (Ultra Giant). Many rogue planets simply turn into frozen wastelands and die, but geologically active planets can maintain a habitable surface via volcanic outgassing and geothermal venting, especially those with satellites, as tidal interactions serve to maintain geothermal activity. While many rogue planets are terrestrial worlds, gas giants are just as likely to be expelled from a star system, and while they are technically Class R, these wandering giants function like any other gaseous world. Often completely uninhabitable, but inhabitable regions may exist	Maybe temperate due to geothermal venting	Primarily volcanic outgassing
Class S (Suk)	Hypergiant Vast planets in a range of colors, bigger by magnitudes than Class J, Class S worlds have near the matter to become stars but -by fluke of stellar formation- have failed. Quite large at 900,000 to 4,160,000 kms radius, their liquid metal core is under such pressure that it can give out its own light that can sometimes flare out of the hydrogen and helium surface. Uninhabitable	Comprised of gaseous hydrogen and hydrogen compounds; radiates considerable heat	Variable pressure and composition; may contain water vapor
Class T (Taurik)	Ultragiant If a Class S planet gains matter by consuming other planets or dust in a star system, it can keep growing to a Class T. These planets are the size of small stars (between 4,161,000 and 5,200,000 kms radius) and are right on the edge of critical mass. Once they reach it, the planet collapses in on itself, becoming a young star. Due to the extremely strong gravimetric sheer that develop between the Class T and its parent star(s), satellites don't tend to get captured by it, but get flung away or pulled right in. Uninhabitable	Comprised of gaseous hydrogen and hydrogen compounds; radiates considerable heat	Variable pressure and composition; may contain water vapor
Class Y (Yen'deshim) (ex: Tholia)	Demon Class Y planets come in a range of sizes (1,000-10,000 kms), and while they have atmospheres, they are completely hostile to almost all known life. Radioactive, toxic air scours the surface at huge speeds. Temperature moves between huge highs and lows, and almost constantly covered in harsh storms, it would be better to be exposed to space than the surface of a Class Y. Uninhabitable	500°K+	Dense to extremely dense and turbulent, saturated with toxic chemicals and therionic radiation
Class Z (ex: Sol V)	Asteroid Belt Asteroid belts are the region of the a star system that inhabit orbits between planets and occupied by numerous irregularly shaped bodies called asteroids or minor planets and can range down to the size of a dust particle. Asteroid belts form from primordial solar nebulae as a group of planetesimals, the smaller precursors of planets, which in turn formed protoplanets; however, gravitational perturbations from large planets, such as gas giants, imbue the protoplanets with too much orbital energy for them to accrete into a planet. Collisions become too violent, and instead of fusing together, the planetesimals and most of the protoplanets shatter, forming an orbital ring of debris. Inhabitable when pressurized	Carbonaceous, silicate and metallic materials	None