Quasar 11

Satellite Data System (SDS) spacecraft are communication relay satellites for transmiting real-time data from US reconnaissance satellites (e.g. KH-11) in polar areas. They are also used for communications to USAF air craft on polar routes and connect the various ground stations of the Air Force Satellite Control Network (AFSCN). The spacecraft relay the downlinked KH-11 data to a ground station at Fort Belvoir, Virginia.