Corona (satellite)#Discoverer
Discoverer is a class of artificial satellites of the Strategic Air Command of the U.S. Air Force ( USA), started from 1959 until 1962.
The term Discoverer was a code name for the Corona program was started at the spy satellites of the type Keyhole. They served, inter alia, the photo-reconnaissance ( IMINT ) of the U.S. Department of Defense. The satellite, developed by GE General Electric, were usually sent with launchers from Thor - Agena on the Vandenberg Air Force Base, California on orbit.