Lockheed Missiles & Space became prime contractor for elements of Military Satellite System (WS 117L), calling for the development of a strategic satellite system. The core element was Lockheed's Agena spacecraft, the world's first multipurpose spacecraft with boost and maneuvering engines, also acting as the 2nd stage of the launch vehicle and/or carrier vehicle for the reconnaissance system. WS-117L and Agena lead to the development of the Corona (satellite)—the nation's first photo reconnaissance satellite system, collecting both intelligence and mapping imagery from August 1960 until May 1972. Over 800,000 images were taken from space, with imaging resolution originally equaling , later improved to . The program was declassified in February 1995. Approximately 365 Agena spacecraft supported a wide variety of missions, from NASA's early interplanetary efforts; to the US Navy's SeaSat, the USAF's Corona, Midas and Samos series between January 1959 and February 1987, when the last Agena D was launched.