Large Areas of Space

System

▪A star and its surrounding planets.

▪Example: "The battle occurs in the Vesper System."

Subsector

▪A collection of neighboring systems.

▪Common in military sci-fi.

▪Example: "The Myr-Valari control the Aurelius Subsector."

Sector

▪Can also represent dozens or hundreds of star systems.

▪Example: "The Orion Sector."

Expanse

▪A vast region of largely unexplored space.