Core worlds

Core worlds or core planets often exist in works of science fiction, especially space operas. They are usually at the center of the galaxy or of colonized space, occasionally both. Core worlds are densely populated with long histories, highly advanced technology, and/or highly developed culture. The capital planets of galactic empires and galactic republics are often core worlds. In many cases, these worlds are considered the economic, cultural and political centers of known space.

A world that is the birthplace of the given race is often known as its homeworld (sometimes abbreviated in fandom as HW) or home planet. For example, Earth is the homeworld of the human race, and the Solar System is its home planetary system (home system) plus the Sun. Note that a homeworld is not necessarily a core world - especially once its natural resources are depleted, and much population emigrates to search for life in space colonies (this is for example the fate of Earth in the fictional universes of Legend of the Galactic Heroes and The Foundation Series).