Adventure in the Spinward Marches
Star Systems and Main Worlds
Star Systems and Mainworlds
Most star systems are identified by their mainworld. That is, the most important planet, moon or planetoid belt in the system. This is for the simple reason that people visit worlds, not stars. The mainworld of a system is usually the most habitable, but not always. It may be a moon of a gas giant or a planetoid belt, but most commonly it will be a planet of some kind.
The nature of the Jump drive is such that unless there is a good (usually economic) reason to visit the other worlds of a system, vessels tend to ply between mainworlds in different systems rather than the less important worlds in the same system. It takes as long to Jump a few hundred AU to an outsystem rockball as it does to travel to the much more important mainworld of the star system a parsec away.
For this reason the remainder of a star system can be quite underdeveloped, though in many cases there will be outposts, mining stations and other installations, not all of them legal or above–board, scattered about the various bodies and planets of a given system.