The KH-4 (Keyhole-4) was fourth version in the Corona-program to build an optical reconnaissance satellite. April 1, 1963 at 23:01 UTC · Launch Successful Thor Agena D — United States Air Force, to Low Earth Orbit Space Launch Complex 1E, Vandenberg SFB, CA, USA The world's 234th orbital launch attempt, and 10th of 1963. Data: Launch Library 2, The Space Devs. Image by USAF via The Space Devs.