Military satellites

A military satellite is an artificial satellite used for a military purpose. The most common missions are intelligence gathering, navigation and military communications. The first military satellites were photographic reconnaissance missions. Some attempts were made to develop satellite based weapons but this work was halted in 1967 following the ratification of international treaties banning the deployment of weapons of mass destruction in orbit. As of 2013, there are 950 satellites of all types in Earth orbit. It is not possible to identify the exact number of these that are military satellites partly due to secrecy and partly due to dual purpose missions such as GPS satellites that serve both civilian and military purposes.

The first military use of satellites was for reconnaissance.

In the United States the first formal military satellite programs, Weapon System 117L, was developed in the mid 1950s. Within this program a number of sub-programs were developed including Corona. Satellites within the Corona program carried different code names. The first launches were code named Discoverer. This mission was a series of reconnaissance satellites, designed to enter orbit, take high-resolution photographs and then return the payload to Earth via parachute.Discoverer 1, the first mission, was launched on 28 February 1959 although it didn't carry a payload being intended as a test flight to prove the technology. The Corona program continued until 25 May 1972. It was abandoned after a Soviet Navy submarine was detected waiting beneath a mid-air retrieval zone in the Pacific Ocean. Corona was followed by other programs including Canyon (seven launches between 1968 and 1977), Aquacade and Orion (stated by US Government sources to be extremely large). There have also been a number of subsequent programs including Magnum and Trumpet, but these remain classified and therefore many details remain speculative.

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