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A celestial body is any object ranging in size from an asteroid to a sun.[1]

The most common size of celestial body is a planetary mass. Celestial bodies come in a large number of shapes although the most common shape is spherical.[1]

Celestial bodies usually have a breathable atmosphere, although bodies without atmospheres or with poisonous atmospheres exist. The depth of an atmosphere is usually related to the size of the body.[1]

Celestial Body Classification[]

Spacefarers use a standard system to categorise celestial bodies.[2]

Size Classes[]

Size classes give information about the diameter of a celestial body:

  • Size A - Less than 10 miles in diameter
  • Size B - 10-100 miles in diameter
  • Size C - 100-1,000 miles in diameter
  • Size D - 1,000-4,000 miles in diameter
  • Size E - 4,000-10,000 miles in diameter
  • Size F - 10,000-40,000 miles in diameter
  • Size G - 40,000-100,000 miles in diameter
  • Size H - 100,000-1,000,000 miles in diameter
  • Size I - 1,000,000-10,000,000 miles in diameter
  • Size J - More than 10,000,000 miles in diameter

Shape Classes[]

Shape classes give information about the general shape of the celestial body:

  • Amorphous (flexible)
  • Belt (smaller objects in a single orbit)
  • Cluster (smaller objects in a small area)
  • Cubic
  • Elliptical
  • Spherical

Two special shape classes exist for planets that do not conform to one of the above shapes:

  • Regular (a regular shape that isn't otherwise listed)
  • Irregular (a shape that isn't listed)

Type Classes[]

Type classes give information about the substance which is most common on the celestial body:

  • Air (also called a gas cloud)
  • Earth (also called a world)
  • Fire (also called a sun)
  • Water (also called a water world)

Some sages add a fifth element:

  • Plant (also called a liveworld)

Supplemental Notes[]

Supplemental notes give additional information about a celestial body. Examples include, but are not limited to:

  • Presence of and number of moons
  • Lack of atmosphere
  • Lethal atmosphere
  • A hollow planet
  • Large extradimensional gates
  • Xenophobic natives (marked by an 'X')

See also[]


  1. 1.0 1.1 1.2 Concordance of Arcane Space, page 6
  2. Concordance of Arcane Space Celestial Body Classification sidebar, pages 34, 36, 38, 40 and 42

External links[]