You can also compare the Sierra System/Sierra Outpost II situation to Bajor and DS9. While those two are clearly easier to tell apart, it does show a "base" in the same system that is a separate navigation point and with all of the other inconsistencies, why not wonder for a moment if "Outpost" implied "Starbase?"
Okay, that about all I felt compelled to spit out in the horse's dying moments.
If you think that's interesting, then you'll love looking for the Afehirr Nebula. It doesn’t appear on your map… galaxy map, yes, but not your local map. At least not for me.. even when you get the mission to explore (which, you Commanders out there, I STRONGLY suggest you do this as you get TONS of Mk V drops – and probably Mk VI as well)