KH-4 CORONA

Corona. Corona refers to the United States program of photo-reconnaissance satellites that was first launched in 1960 and continued in operations till may 1972. It was the first photo-reconnaissance satellite program in the world.

History
The Corona program was signed into effect by President Eisenhower in February 1958 and was the first photo-reconnaissance satellite program any where in the world. The program was designed to gather imagery of the Soviet Union, with an emphasis on the Soviet ballistic missile program.

The Corona program was a joint Defense Department/Central Intelligence Agency program, with the satellites being launched by the United States Air Force. The program was operated under tight security and it wasn't until 1995 that the program was declassified.

The first Corona satellite launch occurred on 28 Feb 1959 and the last one on 25 May 1972. During this time period a total of 145 launches took place. On 18 August 1960, a Corona satellite took the first images from space. In total, 2.1 million feet (800,000 images) of film was taken.

Operations
The Corona satellites was mounted on Thor rocket launchers operated by the U.S.A.F. After launch the satellites were placed in a polar orbit at an attitude of 100 nautical miles (185 km). Once the satellite had taken its pictures the film was ejected from the craft while over the Pacific Ocean where the capsule was snatched up in midair by U.S.A.F. aircraft. The film would then be transported to the facilities where it would be processed and analyzed.

At first image resolution was originally 8 meters (25 feet), with an individual image covering an area of approximately 16 km (10 miles) by 190 km (120 miles). Later improvements in the satellite cameras improved resolution to 2 meters (6 feet).