What are Spy Satellites?
Spy Satellites, also referred to as military reconnaissance and surveillance satellites, operate in many parts of the electromagnetic spectrum. These advanced military satellites are used to observe deployment of military forces, weapons development, assessment of damage caused by bombs and also provide intelligence on enemy capabilities.
The development of reconnaissance satellites was officially demanded by the United States Air Force on March 16, 1955. The main reason for the demand of military reconnaissance satellites was to have a continuous surveillance of some areas to determine the weapons-making capabilities of some potential enemies. The first generation spy satellites were Corona and Zenit.
The Corona was a US military spy satellite system used for photographic surveillance of China, the Soviet Union, and other areas between June 1959 and May 1972. The Corona was operated by the CIA Directorate of Science and Technology, with assistance by the US Air Force.
The Zenit program was a successive launch of military spy satellites between 1961 and 1994 by the Soviet Union. However, the main reason for launching satellites was kept secret.
Reconnaissance satellite missions are varied. The missions range from covert operations and communications to monitoring the nuclear test ban compliance and detecting missile launches.
Long before digital imaging systems came into use, reconnaissance satellites sent vital photographs via canisters. The ejected canisters floated down on parachutes and were retrieved in mid-air. With the transition in technology and imaging systems, spacecrafts started employing digital imaging systems, and the images were downloaded via encrypted radio links.
From Napoleonic times, when the French used observational balloons to scan enemy development, to the current state-of-the-art spy satellites used by powerful nations, the importance of such artificial satellites will always be in great demand for political and military state of affairs.
(Image above, Right: The Zenit Space Vehicle, Photo credit: Maryanna Nesina, http://en.wikipedia.org/wiki/File:Zenit_space_vehicle.jpg)
(Image, Left: The Corona US military spy satellite image courtesy http://www.nro.gov/corona/recsys.jpg)