Ceres (minor planet designation 1 Ceres) is a rocky selenic body in the Sol asteroid belt, and is in fact the largest of the belt objects at approximately 30% of all the mass in the Belt. It is referred to interchangeably as both an asteroid and dwarf planet; while it is roughly spherical under hydrostatics, its composition is highly similar to other asteroidal bodies in the belt. As a planet, its airless, pockmarked surface and volatile composition rank it as an icy selena. In fact, this ice is one of the key traits that render Ceres a crucially important settlement in the Sol system.
Ceres occupies a near-circular, slightly inclined orbit in the main Belt
, with an average solar distance of 2.7 astronomical units. Its inclination, roughly 11 degrees with respect to the ecliptic
, can make interorbital access to the planet somewhat difficult at times. However, its location at the center of the Belt take it past most other main belt objects at various points, making it highly convenient as a base of operations for asteroid mining endeavors.
The dwarf planet itself is rather nondescript in appearance, with a random and more or less even distribution of impact craters across its surface. The poles of Ceres have slightly rougher terrain, whereas the equatorial regions tend to be more level. One of this world's most notable features is Ahuna Mons, a titanic, extinct cryovolcano located just east of Uhola Catenae. The planet's largest settlement, Proserpina, sprawls across the flat expanse of the Kerwan impact basin.
The crust of Ceres is largely composed of clays and other hydrated minerals, a significant portion of which is iron-rich and the rest of which is carbonaceous. This fortuitous combination has led to Ceres' renown as a reliable source of steel in the Sol system. Its vast subsurface reserves of water ice also allow for widespread habitation on and within the surface, in addition to their use as a source of fuel for the chemical rocket engines commonly used for inter-belt navigation.