This is the starbase Reese was docked at when Earthrise opens.
Interestingly, on one map, Fos is up coreward, near Qufiil, while in Earthrise it's obviously somewhere around the spinward border. This is (possibly) a mapping error in the Alliance. If it's not, it needs to be resolved in the canon before it shows up in Alysha's books (or Zafiil's).
- Earthrise Part One