The Space Shuttle flew a total of 135 missions in its lifetime. Of these 135 missions, seven were classified Department of Defense missions whose purposes were never officially announced.* STS-51-C (15th mission, January 1985) deployed a Magnum satellite designed to intercept communications, mainly from the Soviet Union and China. STS-51-J (21st mission, October 1985) deployed … Continue reading The classified Space Shuttle missions