| Description: | Mapping unit in astrography with an average density of 30 to 40 worlds per subsector.
Subsectors are noted within a sector by their position using the first sixteen letters of the alphabet (A-P). In addition, they are named and a variety of other terms may be used, including "province", "cluster", or "district." Imperial convention is to assign numbers to districts (for example, District 268) which are under Imperial protection because they are pending integration into the Imperium. |