TANGO FLEET: SCIENCE CORPS

The official Starfleet planetary classification system, adopted from the Vulcan Science Council in the early days of Starfleet, have become the standard for planetary type identification. The classification information was taken from Geoffrey Mandel's "Star Trek: Star Charts" , which has been accepted for reference purposes in Tango Fleet.
CLASS A - GEOTHERMAL
	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 EXAMPLES Gothos These volcanically active planets are typically small, barren worlds located on the fringes of young star systems. They possess no life forms, and are only able maintain reasonably warm surface temperatures due to the excessive volcanic activity. When this activity ceases, the planet "dies" and evolves into a Class-C planetoid.

CLASS B - GEOMORTEUS
	AGE 0-10 billion years DIAMETER 1,000-10,000 km LOCATION Ecosphere/Cold Zone SURFACE Partially molten; high surface temperature ATMOSPHERE Extremely tenuous; few chemically active gases EVOLUTION N/A LIFE-FORMS None EXAMPLES Mercury, Nebhilum Class B planetoids are generally small worlds located within a star system's Hot Zone. Highly unsuited for humanoid life, Class B planets have thin atmospheres composed primarily of helium and sodium. The surface is molten and highly unstable; temperatures range from 450° in the daylight, to nearly -200° at night. No life forms have ever been observed on Class B planetoids.

CLASS C - GEOINACTIVE
	AGE 2-10 billion years DIAMETER 1,000-10,000 km LOCATION Ecosphere/Cold Zone SURFACE Barren; low surface temperature ATMOSPHERE Frozen EVOLUTION N/A LIFE-FORMS None EXAMPLES Pluto, Psi 2000 These small, rocky worlds frequently exist on the fringes of a star system. They have no geological activity, no life forms, and are essentially dead planets. The tenuous atmosphere is typically frozen, and composed of methane and nitrogen. The surface is barren and cold, with temperatures rarely climbing above -200°.

CLASS D - ASTEROID/MOON
	AGE 2-10 billion years DIAMETER 100-4,000 km LOCATION Hot Zone/Ecosphere/Cold Zone SURFACE Barren and cratered ATMOSPHERE None or very tenuous EVOLUTION N/A LIFE-FORMS None EXAMPLES Eredas-Il, Moon, Lunar V Moons and asteroids are typically found in orbit of larger planets, or in the case of asteroids, within giant asteroid fields. They typically form within asteroid belts, and are captured in the orbit of a larger planets, sometimes forming a ring system. Most Class-D planetoids are not suitable for humanoid life, though they can be colonized through the use of pressure domes.

CLASS E - GEOPLASTIC
	AGE 0-2 billion years DIAMETER 10,000-15,000 km LOCATION Ecosphere SURFACE Molten, high surface temperature ATMOSPHERE Hydrogen compounds and reactive gases EVOLUTION Cools to become Class-F LIFE-FORMS Carbon-cycle EXAMPLES Excalbia Nearly all Class-M planets begin life as a Class-E world. In this earliest stage of life, the planet's core and crust is completely molten, with very high surface temperatures, and an atmosphere made of hydrogen and helium. Because of this, Class-E planets do not have a magnetic field, making them susceptible to solar winds and radiation. Class-E planets cool to become Class-F.

CLASS F - GEOMETALLIC
	AGE 1-3 billion years DIAMETER 10,000-15,000 km LOCATION Ecosphere SURFACE Volcanic eruptions due to molten core ATMOSPHERE Carbon dioxide, ammonia, methane EVOLUTION Cools to become Class-G LIFE-FORMS Bacteria EXAMPLES Janus IV As a Class-E planet cools, the eruption of massive volcanoes mark the transition to Class-F. In this stage of life, the molten core gradually begins to solidify. Additionally, steam expelled in the numerous volcanic eruptions condenses into water, givingrise to shallow seas in which simple bacteria thrive.

CLASS G - GEOCRYSTALLINE
	AGE 3-4 billion years DIAMETER 10,000-15,000 km LOCATION Ecosphere SURFACE Rocky, still crystallizing ATMOSPHERE Carbon dioxide, some oxygen and nitrogen EVOLUTION Cools to become Class-H, K, L, M, N, O, or P LIFE-FORMS Some vegetation, single-celled organisms EXAMPLES Delta Vega When a planet's core cools sufficiently, it makes the transition to Class-G. The surface of these planetoids is still in the process of solidifying, but primitive vegetation, such as algae, have already begun the process of photosynthesis. Once enough oxygen is released into the atmosphere, Class-G planets typically form an ozone, which in turn allow for the growth of more complex life forms.

CLASS H - DESERT
	AGE 4-10 billion years DIAMETER 8,000-15,000 km LOCATION Hot Zone/ Ecosphere /Cold Zone SURFACE Hot and arid; little or no surface water ATMOSPHERE May contain heavy gases and metal vapors EVOLUTION Cools to become Class-G LIFE-FORMS Drought- and radiation-resistant plants, animals, humanoids EXAMPLES Dimovius, Gildebron III, Nimbus III, Corneria Though most Class-H planets are vast oceans of sand, it is water and that determines its classification. Any planet whose surface is less than 80% water is deemed Class-H. Rainfall is rare on such planetoids, with temperatures frequently reaching 60° or higher. However, not all deserts are warm and sandy. Many Class-H planets in a star system's cold zone are rocky and barren, with extremely low temperatures. Class-H atmospheres can vary greatly; most contain oxygen and nitrogen, but high amounts of argon are not uncommon.

CLASS I - GAS SUPERGIANT
	AGE 2-10 billion years DIAMETER 140,000-10 ,000,000 km LOCATION Cold Zone SURFACE Tenuous liquid hydrogen ATMOSPHERE Variable; generally hydrogen and helium EVOLUTION N/A LIFE-FORMS None EXAMPLES Q 'tahL These massive planetoids typically have a solid, rocky core that is surrounded by metallic and then liquid hydrogen. They hydrogen gradually becomes gaseous, but there is no distinct boundary. Class-I planets typically have very short days, often completing one revolution in less than ten hours. This causes the planets to become slightly flattened, a feature also seen in J-, S-, and T-Class planets. The atmosphere is turbulent; wind speeds in some storms have exceeded 800 kph.

CLASS J - GAS GIANT
	AGE 2-10 billion years DIAMETER 50,000-140,000 km LOCATION Cold Zone SURFACE Tenuous liquid hydrogen ATMOSPHERE Variable; generally hydrogen and helium EVOLUTION N/A LIFE-FORMS Hydrocarbon-based EXAMPLES Jupiter, Saturn Also known as Jovian planets (after Jupiter), Class-J worlds are massive spheres of liquid and gaseous hydrogen, with trace amounts of helium, methane, and water vapor. Atmospheric wind speeds in excess of 600 kph are not uncommon. Many Class-J planetoids possess large ring systems, generally composed of ice, dust, and small rocks.

CLASS K - ADAPTABLE
	AGE 4-10 billion years DIAMETER 5,000-10,000 km LOCATION Ecosphere SURFACE Barren, little or no surface water ATMOSPHERE Thin, mostly carbon dioxide EVOLUTION N/A LIFE-FORMS Primitive single-celled organisms EXAMPLES Mars, Mudd, Elba II Though similar in appearance to Class-H worlds, Class-K planets lack the robust atmosphere of their desert counterparts. Though rare, primitive single-celled organisms have been known to exist, though more complex life never evolves. However, humanoid colonization is possible through the use of pressure domes and in some cases, terraforming.

CLASS L - MARGINAL
	AGE 4-10 billion years DIAMETER 10,000-15,000 km LOCATION Ecosphere SURFACE Rocky and barren; little surface water ATMOSPHERE Argon, oxygen, trace elements EVOLUTION N/A LIFE-FORMS Limited to vegetation EXAMPLES Alarin III, Ciden II, Indri VIII Devoid of sentient life, Class-L planets are suitable for humanoid colonization, and are prime candidates for terraforming. Temperatures are cool, rarely exceeding 15°, and water is generally scarce. Hardy vegetation is not uncommon, though few Class-L worlds boast an impressive ecosystem.

CLASS M - TERRESTRIAL
	AGE 3-10 billion years DIAMETER 10,000-15,000 km LOCATION Ecosphere SURFACE Abundant surface water; temperate climate ATMOSPHERE Nitrogen, oxygen, argon, trace elements EVOLUTION N/A LIFE-FORMS Extensive vegetation, animal and humanoid life EXAMPLES Earth, Vulcan, Bajor, Tellar, Risa Also known as Minshara Class planets, Class-M worlds are robust and varied planetoids that are highly suitable for humanoid life. While they can vary widely in appearance, all Class-M planetoids have breathable atmospheres and surface temperatures near 25°. Class-M planets are characterized by a tectonically active crust floating on a molten rock mantle.

CLASS N - REDUCING
	AGE 3-10 billion years DIAMETER 10,000-15,000 km LOCATION Ecosphere SURFACE Barren; high surface temperature ATMOSPHERE Extremely dense; carbon dioxide and sulfides EVOLUTION N/A LIFE-FORMS None EXAMPLES Venus Though frequently found in the Ecosphere, Class-N planets not conducive to life. The terrain is barren, with surface temperatures in excess of 500° and an atmospheric pressure more than 90 times that of a Class-M world. Additionally, the atmosphere is primarily composed of carbon dioxide; water exists only in the form of thick, vaporous clouds that shroud most of the planet.

CLASS O - PELAGIC
	AGE 3-10 billion years DIAMETER 10,000-15,000 km LOCATION Ecosphere SURFACE Liquid water with many archipelagos ATMOSPHERE Nitrogen, oxygen, trace elements EVOLUTION N/A LIFE-FORMS Extensive vegetation, animal and human life EXAMPLES Azati Prime, Ka'Tula Prime, Zirat Any planet whose surface is more than 80% liquid water is considered Class-O. These watery worlds are usually warm, and possess robust aquatic ecosystems. To a lesser extent, humanoid populations inhabit the many archipelagos, the Xindi and the Ka'Tulans being the most notable species to do so.

CLASS P - GLACIATED
	AGE 3-10 billion years DIAMETER 10,000-15,000 km LOCATION Ecosphere SURFACE Mainly frozen water ATMOSPHERE Nitrogen, oxygen, trace elements EVOLUTION N/A LIFE-FORMS Hardy vegetation, animal and human life EXAMPLES Andoria, Exo III, Rebena Te Ra, Rura Penthe Any planet whose surface is more than 80% frozen is considered Class-P. These glaciated worlds are typically very cold, with temperatures rarely above 0°. Though not prime conditions for life, many species, including the Andorians and the Aenar, have evolved on Class-P worlds.

CLASS Q - VARIABLE
	AGE 2-10 billion years DIAMETER 4,000-15,000 km LOCATION Hot Zone/Ecosphere/Cold Zone SURFACE Ranges from molten to carbon-dioxide ice ATMOSPHERE Ranges from tenuous to very dense EVOLUTION N/A LIFE-FORMS None EXAMPLES Genesis Planet These rare planetoids typically develop with a highly eccentric orbit, or near stars with a variable output. As such, conditions on the planet's surface are widely varied. Deserts and rain forests exist within a few kilometers of each other, while glaciers can simultaneously lie very near the equator. Given the constant instability, is virtually impossible for life to exist on Class-Q worlds.

CLASS R - Rogue
	AGE 2-10 billion years DIAMETER 4,000-15,000 km LOCATION Interstellar space, cometary halos SURFACE May be temperate due to geothermal venting ATMOSPHERE Primarily volcanic outgassing EVOLUTION N/A LIFE-FORMS Non-photosynthetic plants, animal life EXAMPLES D akala, Founders' Homeworld (prior to 2371) Class-R planets usually begin life within the confines of a star system, but at some point in its evolution, the planet is expelled, possibly by a colossal asteroid or some other phenomenon. This shift radically changes the planet's evolution; many simply die, but geologically active planets can sustain themselves via volcanic outgassing.

CLASS S-T - ULTRAGIANT
	AGE 3-10 billion years DIAMETER 10 ,000 ,000-5 0 ,000 ,000 km (Class-S) _________50,000,000-120,000,000 km (Class-T) LOCATION Cold Zone SURFACE Tenuous liquid hydrogen ATMOSPHERE Variable; generally hydrogen and helium EVOLUTION N/A LIFE-FORMS None EXAMPLES Tethe-Alla V A side from their incredibly massive size, Class-S and Class-T planetoids are generally similar to smaller Class-I and Class-J counterparts.

CLASS Y - DEMON
	AGE 2-10 billion years DIAMETER 10,000-15,000 km LOCATION Hot Zone SURFACE Barren; temperatures can exceed 500° ATMOSPHERE Turbulent; saturated with toxic radiation EVOLUTION N/A LIFE-FORMS Mimetic EXAMPLES Silver Blood Planet (VOY) Perhaps the most environmentally unfriendly planets in the galaxy, Demon-class worlds are toxic to life in every way imaginable. The atmosphere is toxic, temperatures are extreme, and atmospheric storms are amongst the most severe in the galaxy, with winds in excess of 500 kph.