"DoD's SSN" . "space surveillance system" . "US Space Surveillance Network" . "space surveillance network" . "optical" . . "USAF SPACETRACK network" . . "U.S. Space Surveillance Network" . . "U.S. space surveillance network" . "AN/FPS-80" . "FPS-79" . . "Department of Defense Space Surveillance Network" . . "Space Surveillance Radar" . . "Space Surveillance Network" . "Ground-based Electro-Optical Deep Space Surveillance" . "United States Space Surveillance Network" . "SSN" . . "AN/FPS-80M" . "Space Surveillance" . . "spacecraft tracking" . "United States Space Surveillance Network#Space Surveillance Telescope program" . "space surveillance" . "United_States_Space_Surveillance_Network#US_Space_Catalog" . "United States Space Surveillance Network#AN/FPS-80" . "United States Space Surveillance Network#Ground-based Electro-Optical Deep Space Surveillance" . "ballistic missile warning and space surveillance facilities" . "GEODSS" . "United States Space Surveillance Network" . "orbiting space object information" .