Science Fair Project Encyclopedia
Spy satellite
A spy satellite (officially referred to as a reconnaissance satellite or recon sat) is an Earth observation satellite or communications satellite deployed for military or intelligence applications. Until the 1970s and even the 1980s, many reconnaissance satellites that took photographs would eject canisters of photographic film, which would descend to earth and be retrieved in mid-air as they floated down on parachutes.
The term "reconnaissance satellite" is preferred, as "spy satellite" often has negative connotations.
In the United States, the most information is available on programs that existed up to 1972. Some information about programs prior to that time is still classified, and a small trickle of information is available on subsequent missions. A few up-to-date reconnaissance satellite images have been declassified on occasion, or leaked, as in the case of KH-11 photographs which were sent to Jane's Defence Weekly in 1985.
Examples of reconnaissance satellite missions:
- high resolution photography (IMINT)
- communications eavesdropping (SIGINT)
- covert communications (HUMINT)
- enforcement of nuclear test bans
- detection of missile launches
Types of spy satellites
Key Hole (KH) series of imaging satellites:
Time period Designation Code name
or NicknameOptics Notes 1959–1972 KH-1 to
KH-4Corona Resolution: 7.5 m, 2.75 m, 1.8 m
Focal length: 0.6 mFirst known series of US spy satellites; photographs returned by film canister ejection. 1960–1962 – Samos Res: 30 to 1.5 m
Foc len: 0.7 to 1.83 mMost flights used radio to relay images; some film returns; probably cancelled due to poor-quality imagery 1961–1964 KH-5 Argon Res: 140 m
Foc len: 76 mmFilm return 1963 KH-6 Lanyard Res: 1.8 m
Foc len: 1.67 mShortlived operation for imaging a specific site; used a camera from the Samos program; film return 1963–1967 KH-7 Gambit Res: 0.46 m Film return 1966–1984 KH-8 Gambit Res: 0.5 m Film return 1971–1986 KH-9 Hexagon
Big BirdRes: 0.30 m Film return cancelled KH-10 Dorian Manned Orbiting Laboratory; space station based on Gemini program 1976–1995 KH-11 Crystal
KennanRes: 0.15 m
Mirror: 2.3 mFirst known digital imaging spy satellite. 1990?–present? KH-12 Ikon
Improved CrystalRes: 0.15 to 0.10? m
Mirror: 2.4 to 4? mDigital imaging; possible "live" intelligence gathering 1999?–present? KH-13 8X? EIS? Res: 0.10? to 0.04? m
Mirror: 4? mVery little known; possibly includes radar imaging or maybe stealth technology
See also
External links
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