World Classification

Inhabited space contains countless millions of planets and planet-like bodies, in order to help easily distinguish between them, a classification system has been agreed upon by most nations.

This catalogue only includes worlds that 1) Are sufficiently massive to assume a spherical shape due to their own gravity and 2) have or have had an active internal geology that lasts one million years or more. For other worlds see Gas Giant Classification and Planetoid Classification. Each world has a type describing it's composition and a class describing it's surface conditions, and a prefix decribing any special characteristics, in the event that multiple types, classes or prefixes apply to a single planet, the most specialised one takes precedence.


  • Carbonean Type, worlds composed primarily out of carbon.
  • Ferrinian Type, worlds composed primarily out of iron and ferrous materials.
  • Ymerian Type, worlds composed primarily out ices.
    • Europan Subtype, worlds with an icy surface that cover liquid subcrustal oceans.
  • Silician Type, worlds composed primarily out of rock and other silicates.


  • Arean Class, worlds with little to no atmosphere or magnetic field.
  • Gaian Class, worlds of roughly earth-like size and atmospheric pressure.
    • Chlorogaian subclass, Gaian worlds with very high concentrations of chlorine in the atmosphere.
    • Pelagic subclass, Gaian worlds with more than 85% ocean coverage.
    • Xeric subclass, Gaian worlds with less than 25% ocean coverage.
    • Postgaian subclass, Gaian worlds that have lost large parts of their atmo- and hydrosphere due to stellar wind.
  • Hepheastian class, worlds with hot surfaces consisting almost entirely out of molten material.
  • Chthonian class, postjovian worlds that had their atmosphere stripped away, leaving only a rocky or metallic core.
  • Cytherean Class, worlds with an extremely high atmospheric pressure.


  • Li, worlds hosting life.
    • Eu, worlds capable of supporting most common forms of carbon-based life.
    • Ci, worlds with a population of over three billion.
    • Da, worlds with native complex life.
  • Lo, worlds that have been tidally locked to their parent gravity well, with one side of the planet always facing it.


  • Earth, a Ferrinean type CiGaian world.
  • Tys, a Silicean type CiXeric world.
  • Venus, a Ferrinean type Cytherean world.