The KH-4B was the last and most advanced camera system used in Project Corona, America and the world's first photoreconnaissance satellite program. Between August 1960 and May 1972, when the program ended, 145 Corona satellites were launched and they produced over 800,000 usable images of the USSR and other nations. Film return capsules containing the exposed film separated from the spacecraft in orbit, reentered the atmosphere, and were retrieved in midair. The Itek-made KH-4B camera was used from 1967 until the end of the program and under ideal conditions produced a ground resolution of 6 feet. This artifact was reconstructed from spare parts and was transferred to NASM by the National Reconnaissance Office in 1995.