- Also see List of sectors.
In Star Trek Online, a sector is a unit of spatial measurement with a size of 20x20x20 light years, and is a subdivision of a quadrant in the galaxy. Each sector contains several objects, first and foremost star systems, and is navigable via sector space, which is like an overview map.
Until the sector space revamp with Season 10, sectors used to be grouped into "Sector blocks". While these blocks do not exist anymore, borders between sectors still determine which Duty officer assignments are available to the player and which (if any) sector space contacts are available.