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• NoLWoCS is divided into three tiers of classification: Class, Type, and Subtype. The different Classes of worlds are dependent on size, overall characteristics, and status of a planet. For instance, Planetoidal and Terrestrial world Classes are divided according to size, just as Terrestrial and Jovian worlds are different Classes because of their general characteristics, and of course, artificial worlds are different from all of these because they are not naturally occurring.

• World Types are dependant on a variety of factors, but generally the compositional elements, which often lead to different planetary features and behaviors, are of sufficient difference to separate these worlds. Subtypes are much more specific, and often are the result of what would normally be considered minor planetary features. For instance, Gaian worlds are divided into several different Subtypes based on items such as the amount of surface water, atmospheric composition, and so on.

Image from Steve Bowers

Blueglass - a tidally-locked entstatian gas giant,which is hot enough at the epistellar point to produce blue-gray silicate clouds

Planetary Cloud/Haze Types and Temperature Regimes

• Cryoazurian Type Clarified: Below 60 Kelvin, no visible clouds and only faint organic hazes. Dull blue in color.
• Methanean Type Clouds: Worlds between 55 and 105 Kelvin, hosting clouds of methane and ethane. Stratospheric cirrus clouds of argon and organic hazes are also commonly found on these worlds. Methanean clouds are usually white-turquoise in color.
• Tholian Type Haze: Hazy worlds between 60 and 400 Kelvin, sporting various types of organic hazes. These worlds are usually a pale yellow, orange, or brown.
• Ammonian Type Clouds: Worlds hosting ammonia and ammonium hydrosulfide clouds. They can be found at temperatures between 75 and 190 Kelvin. Ammonian clouds can be cream, beige, or peach in color. Organic compounds can result in an orange, brown, or gold tinge. Ammonia clouds form at colder temperatures than ammonium hydrosulfide, and dominate the appearance below around 100 Kelvin.
• Aquean Type Clouds: These temperate worlds between 175 and 360 Kelvin have clouds of water vapor. Aquean clouds are predominantly white, but can take on a slightly brown, blue, or grey color.
• Acidian Type Clouds: Warm worlds between 200 and 570 Kelvin that have high metallicities. Clouds are dominated by sulfuric acid, less commonly phosphoric acid or monoammonium phosphate. Water can also be present on acidian worlds, but is usually restricted to cirrus clouds due to the higher temperatures. Acidian clouds are usually tan, taupe, or beige in color.
• Mesoazurian Type Clarified: Worlds with no high altitude clouds and minimal organic and organosulfur hazes, between around 400 and 700 Kelvin. Dull blue to teal in color.
• Silicolean Type Haze: Worlds with hazes of silicone oils, fluorosilicones, and other organosilicon compounds, occurring between 550 and 1000 Kelvin. Light brown or grey in color.
• Chloroalkalinean Type Clouds: Worlds between 620 and 900 Kelvin with clouds of alkali metal chlorides. Potassium chloride is the most common of these, and may also be accompanied by other metal compounds with similar condensation curves such as zinc sulfide. These clouds can be bronze or pale green in color.
• Sulfoalkalinean Type Clouds: Worlds between 800 and 1100 Kelvin with alkali metal sulfide clouds. There is significant overlap between sulfoalkalinean and chloroalkalinean clouds, with sulfoalkalinean clouds being significantly hotter. The most common compounds in these clouds are sodium sulfide, lithium sulfide, and lithium fluoride. These clouds are dark brown or grey in color.
• Pyroazurian Type Clarified: Worlds between around 1100 and 1400 Kelvin with no visible clouds or hazes. Can be dull to deep blue depending on the level of impurities.
• Erythronian Type Clouds: Worlds between 1150 and 1500 Kelvin, possessing clouds of Manganese oxides and sulfides, as well as metallic chromium. Some erythronian worlds are hot enough to host titanium and vanadium oxide hazes instead of organosulfur compounds. Clouds of this type appear dull red to dark orange in color.
• Enstatian Type Clouds: Worlds with clouds composed of rocky and metallic compounds, usually iron and magnesium silicates. These worlds occur at temperatures between 1200 and 1900 Kelvin, and are predominantly grey with a green, blue, or brown tinge.
• Rutilian Type Haze: Hazes of titanium and vanadium oxides occurring between about 1450 and 2000 Kelvin. These worlds are dark grey to black in color.
• Refractian Type Clouds: These clouds occur between 1700 and 2350 Kelvin. They are comprised of various refractory oxides, such as calcium titanate, calcium aluminate, corundum, as well as vanadium and titanium oxides. These clouds are usually pale red, orange, brown, or pink.

Asteroids

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ASTEROID CLASS: non-spherical worlds of extremely low mass

Types of Asteroid

• Carbonic: Almost exclusively of carbon compound construction, resulting in the formation of bodies from pockets of high carbon material around later generation stars choked with heavier elements; common near the galactic core. They may also form in systems where two white dwarfs have spiralled together, and the resulting circumstellar disk coalesces into bodies high in carbon.
• Metallic: More Information here
• Carbonaceous: More Information here
• Silicaceous: More Information here
• Hydronic: Located close to the system's snow-line, these are silicaceous bodies with high instances of subsurface volatiles, typically in the form of water ice. Polar deposits in permanently shadowed regions may also be present.
• Gelidic: Located beyond the snow line of their system, these are bodies with high instances of ice, ranging from water to methane to carbon dioxide, and many other compounds besides, surrounding a core of silicate rock. The smaller bodies may be a nearly homogeneous mixture of ice and rock, due to the lack of a mass great enough to have caused layer differentiation early in the formative period. See also Centaurian Type
• Oortean: More Information here.
• Vulcanian: More Information here.

Minor Planets (Planetoids)

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PLANETOID CLASS: worlds with enough mass to pull themselves into spherical or near-spherical shapes

Types of Planetoid

• Carbonean type: Carbon worlds of this mass have a chance to form around stars whose proto-stellar disks have developed carbon pockets within them, but they are far more common about late generation, high metal stars or even as the results of secondary planetary formation around high carbon stars such as white dwarfs. However, worlds of this size and mass also experience some differentiation during their formation. The cores of such worlds are dense masses of condensed graphite, though the planetoids at the higher mass range could form cores of partially crystallized diamond.
• Hadean Type: More Information here.
• Hygiean: These bodies are typically quite dark, with albedos ranging from 0.03 to 0.1. While there can be deposits of water ice or other volatiles beneath the surfaces of these planetoids, the surfaces are more often marked by craters and large boulders. These worlds are less dense and more easily disrupted by major impacts. The larger bodies, however, will have been differentiated through the formation process, and can have small cores of iron, with a dense mantle or rock and a crust of lighter silicates. The smaller worlds, though, may be a relative even mixture of sparse metals and the far more common silicate rock.
• Cerean Type: More Information here.
• Chronian type: Named after the plethora of such bodies orbiting the planet Saturn, these can be a highly varied lot. Typically, these worlds are small and heavily cratered bodies untouched by time, save for the numerous impacts that they have suffered. Their low mass and composition of primarily ice, with small rocky cores, are simply too small for sustained geological activity. As such, there is an absence of atmosphere, or related surface features. However, certain disruptions, such as through tidal flexing or other massive external forces may initiate geological forces that can completely resurface a planetoid, as well as form a minor atmosphere. If such active worlds are positioned properly in a gas giant system, an impressive ring system may even be formed.
• Vestian Type: More Information here.
• Kuiperian Type: More Information here.

Terrestrial worlds

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TERRESTRIAL CLASS: worlds with an active internal geology that lasts one million years or more: 0.05 to 2.5 x Earth's mass

• Adamaean: Carbon Worlds. Carbon-rich terrestrials. More information here
• Ferrinian: Iron-rich, dense worlds. More information here
• Hermian: Dense, inner system worlds. More information here
• Selenian: Worlds with little or no metallic core.More information here
• Cytherean: Hot, greenhouse worlds. More information here.
• PelaCytherean: Terrestrial sized hot ocean worlds with thick atmospheres. More information here.
• LithicGelidian: Worlds with a mixed rock and ice composition. More information here.
• Europan: Icy worlds with a subcrustal ocean. More information here.
• Titanian: Icy worlds with thick atmospheres. More information here.
• Ymirian: Worlds made almost entirely of ices. More information here.
• Vesperian: Tidally locked terrestrial worlds. More information here.
• Hephaestian: These are the most active of planets, with surfaces that are almost entirely molten and a geology that changes on a yearly basis. The atmospheres of these planets vary greatly according to the world's size and mass, from having thick, Cytherean-like atmospheres to almost non-existent ones, where the feeble gravity loses any elements almost as soon as they are released from the surface. These worlds are generally heated by tidal flexing, by proximity to a star or as a moon of a gas giant. Example: Io.
• Amunian Type: Cold, dry worlds with high levels of ammonia in the atmosphere but little water. May develop an ammonia-based biosphere (see the Soft Ones xenosophonts for one example).
• Vitriolic Type: Worlds with lakes, seas or oceans of sulphuric acid; often with life, More information here.

Image from John M Dollan

• Arean type: Mars-like worlds where the atmosphere and hydrosphere has largely disappeared due to the cessation of magnetic activity. .More information here.
• EoArean subtype Young Mars-like Type planet with substantial atmosphere and surface water. More information here
• AreanLacustric subtype: Young Mars-like worlds with moderate amounts of ocean cover . More information here.
• AreanXeric subtype Mature, unusually hot and dry Arean type worlds. More information here.
• AreanTundral subtype Cold Arean type worlds, often with considerable reserves of ice More information here.
• EuArean Subtype Typical mature Mars-like world with minimal atmosphere and hydrosphere More information here.

Image from Steve Bowers

Earth-like Worlds

• Gaian Type: Any Earth-like terrestrial world, of which there are many diverse forms depending on water content, composition and temperature. More information here
• EoGaian Subtype: Young terrestrial worlds; these may develop into Gaian, Cytherean or Arean worlds later More information here
• MesoGaian Subtype: Earth-like worlds with primitive biospheres More information here
• Eugaian Subtype A mature Gaian world with life, also known as a Garden World More Information Here
• GaianTundral Subtype: Cold Gaian worlds with periodic, or persistent, ice ages More Information Here
• Campian Subtype: Dry Gaian worlds with 25% to 50% ocean cover More Information Here
• Paludial Subtype: Humid Gaian worlds with 25% to 50% ocean cover More Information Here
• Lacustric Subtype:Humid Gaian worlds with low topography and 50-80% ocean coverage; some of these worlds have extensive rainforest-type biomes More Information Here.
• Chlorogaian (Halogenic) type: Gaian worlds with high levels of atmospheric chlorine. More: Chlorine Worlds.
• To'ul'hese Worlds: These worlds are essentially Gaian versions of the Cytherean worlds. Thick and dense atmospheres, as well as a large amount of water, create high surface pressures and high temperatures. Life arises and adapts to these conditions, and can become quite diverse indeed. In one known instance, it has lead to an independent form of sapient life. More: To'ul'hian Worlds.
• Pelagic Subtype Gaian worlds where oceans cover the surface anywhere from 80 to 100%. More Information here
• EuPelagic Subtype Gaian worlds where shallow oceans cover the surface anywhere from 80 to 100%. More information here
• BathyPelagic Subtype: Gaian worlds where deep oceans cover the surface anywhere from 80 to 100%. More information here.
• PelaGelidic Subtype, ice covered ocean worlds More information here.
• TundralPelagic subtype, partially ice covered ocean worlds More information here.
• Xeric subtype Dry worlds with less than 25% ocean cover More information here.
• HyperXeric subtype Very dry worlds with less than 10% ocean cover More information here.
• PostGaian subtype: Old Gaian Worlds that are losing their biosphere and hydrosphere More information here.

Superterrestrials

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SUPER-TERRESTRIAL CLASS: worlds that are moderately massive, intermediate in mass between Terrestrial worlds and Neptunian worlds

• Pyrothalassic Type: Hot superterrestrials More information here
• Pyrohydrothallasic Type - Hot waterworlds More information here
• Panthalassic Type: Giant Waterworlds More information here
• Nebulous Type: Superterrestrials with thick, helium-rich atmospheres. Helium worlds of this kind (generally known as Helian Worlds) often have superrotating atmospheres; those which are tidally locked often have wildly assymetric weather patterns.
• Gas Dwarfs: worlds smaller than 0.03 x the mass of Jupiter which nevertheless have thick atmospheres consisting mostly of hydrogen and helium. Gas-rich worlds with more than 50% water/ice are classified as ocean worlds, either pyrohydrothallassic or panthallassic according to temperature.
• Other types of superterrestrial planets include certain hyperbarian and chthonian worlds, some of which have very sparse atmospheres indeed.

Neptunian Worlds

Neptunian Worlds

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An AzuriNeptunian world

Gas Giants

Gas Giants

Image from John M Dollan

Gas Giant Classes

• Microjovian Type Jovian worlds with masses from 0.03 to 0.21 that of Jupiter, but less than 50% water More Information here.
• Mesojovian Type Jovian worlds with masses from 0.21 to 8.0 that of Jupiter More information here.
• SuperJovian Type Jovian worlds with masses from 8.1 to 13.0 that of Jupiter, the theoretical upper limit of planets. Objects more massive than this are classed as Brown Dwarfs. More information here.
• See also Gas Dwarfs.

Gas Giant Temperature Types

• HyperthermalJovian Type: Very hot gas giants, with temperatures above 1400 Kelvin. Includes so=called 'Puffy worlds' and 'Comet worlds'. More Information here.
• EpiStellar Jovian Type: Hot, dark gas giants with temperatures between 900 Kelvin and 1400 Kelvin. More information here
• AzuriJovian Type Warm clarified blue gas giants with temperatures between 350K and 800K. More information here.
• HydroJovian Type: Temperate gas giants with clouds predominantly consisting of water vapour. More information here.
• EuJovian Type: Cool gas giants, with clouds predominantly consisting of ammonia. More information here.
• CryoJovian Type: Cold gas giants in the outer reaches of a planetary system, generally too cold for clouds to form at all. More information here.

Other World Classes

• HyperBarian Class: Very dense planets with cores up to 100 x Earth's mass. More information here.
• Chthonian Class: Gas giant worlds, formerly HyperthermalJovians, which have lost their volatiles through evaporation. More information here.
• Stevensonian Class Planetary mass objects which are found in interstellar space. More information here.

World types distinguished by their orbital and rotational parameters

Eccentric worlds and Tilted Worlds

• Skolian Type Worlds Worlds with axial tilts greater than 45 degrees; any class of world can have Skolian characteristics. More information here
• Janusian Type Worlds Worlds in resonant orbits which regularly exchange momentum. More Information here
• Ikarian type worlds Worlds with eccentric orbits, with an eccentricity greater than 0.35. Any class of world can have an Ikarian type orbit. More Information here.

ARTIFICIAL CLASS

• Rotating Space Habitats Habitats constructed using conventional materials - includes Paired Habitats, Stanford Tori, O'Neill Cylinders, Bernal Spheres, Bishop Rings. More information Here.
• Banks Orbitals and Ringworlds - Rotating habitats made from exotic materials (see Banks Orbitals).
• Non Rotating Space Habitats - often used by space adapted clades; can be very large, but they are limited by their density- if they are too dense they will undergo self-gravitational collapse. More information here.
• Ederworlds More information here.
• Supermundane Worlds -worlds dynamically suspended above planets and stars. More information here
• Freespheres - microgravity balloons containing atmosphere -can be very large indeed. More information here.
• Dyson Swarms and Spheres Many variants of this type of construct are described here.

• Arean Type planet
• Artificial Planets
• Artificial Worlds
• Asteroid
• CADRS Planetary Classification System, The
• Extended World Classification System (EWoCS)
• Gaian Type
• Planetoid Class
• Superterrestrial Worlds