B9J-NT constellation

A constellation is the middle layer of New Eden: a region holds constellations, a constellation holds solar systems. In null security space it is also the unit people fight over - sovereignty, staging and the stations that go with it tend to move a whole constellation at a time.

Systems of one constellation are neighbours in the truest sense: most gates inside it lead to another system of the same constellation, so a fleet camping one of them shapes traffic through all of them.