Celestial body

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

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.

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.

Celestial Body Classification
Spacefarers use a standard system to categorise celestial bodies.

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