A secret Section 31 base in a former penal colony ringed by mines, where Discovery's crew found the staff dead and the artificial intelligence Control in command in 2257.
Section 31 Headquarters, as seen in the Discovery episode Project Daedalus, is a space station that once served as a penal colony. Section 31 took it over as its seat of operations, and it houses Control, the threat-assessment system on which Starfleet's admirals had come to rely. A field of blade-like mines surrounds it.
Admiral Katrina Cornwell guides the USS Discovery through the minefield so that she can confront the organisation's leadership. An away team of Burnham, Nhan and Airiam finds the life support shut down and the admirals dead for weeks; Control had been impersonating them with holograms.
Control then uses the cybernetically augmented Airiam, whom it had compromised, to try to obtain the sphere's archive of data. Unable to stop herself, Airiam asks to be blown out of the airlock.