KH-6 (Keyhole 6, codenamed Lanyard) was a part of the Corona program and aimed to capture higher resolution imagery. Equipped with a modified Samos E-5 camera built by Kodak, the KH-6 camera could tilt between fore and aft to acquire stereo coverage of the same land area during a photographic pass. With a ground resolution of approximately 1.8 meters, the KH-6 sought to improve image quality significantly. These satellites were designed for film capsule deorbiting from space, with mid-air recovery facilitated by specially equipped aircraft.

The Hitchhiker satellites were prototype satellites in the P-11 program, which served scientific purposes. Later P-11 satellites were built as classified SIGINT subsatellites.