Corona (satellite)

Keyhole (English for peephole, literally keyhole ) or abbreviated KH refers to a series of types of U.S. optical spy satellites. A total of 287 satellites of the KH series were launched. Originally, however, Keyhole designated only the security system should be kept secret with the satellite images.

KH -1, -2, -3, -4, -4A, -4B Corona

The first satellite ( the types KH- 1 to KH -4B ) were also called Corona. The cameras of these satellites have resolutions of 7.5 m initially, later up to 1.5 m. Your orbit had an apogee after the start of 460 km and a perigee of about 165 km. The images were recorded on a standard film. KH -4 took off in 1962 as the first satellite and stereoscopic pictures. Target area of the satellites were mainly the USSR and the People's Republic of China. By no later than 1967, the Middle East has been repeatedly observed, such as those recorded before and were compared after the Six Day War. Because the transmission of images over wireless is not as well developed and was not yet sufficiently bug-proof, the films with re-entry capsules that were still hanging intercepted by parachute in the air from an aircraft were returned to Earth.

The type KH -4B had two panoramic cameras with aperture of 1:3.5 and 24 inches ( 61 cm) focal length and an index - camera ( for an overview ) on. During 19 days of mission duration were up to 9,600 m, 70-mm film (almost always black and white) exposed and rewound into the cartridge of the two return capsules. After separating a capsule whose first rotation and then the airspeed was slowed down with a rocket engine. When re- entering the atmosphere at first slowed the shock wave, then - with removal of the heat shield - a small drogue parachute, most recently a main parachute, which is only in 15,000 m completely open before screen and capsule is fished up in the air from an airplane.

The first launch of Corona satellite found in early 1959 under the pseudonym instead of Discoverer, the first car equipped with camera satellite was launched in June of the same year as Discoverer 4 ( mass 750 kg), but yielded no usable images. The first usable images delivered on August 19, 1960 Discoverer 14 The name was Discoverer Discoverer to 38 in 1962 used. A total of 145 Corona satellites were launched with various variants of the Thor - Agena rocket from 1959 to 1972, of which yielded 102 usable images.

KH -5 Argon

KH -5, also known as argon, was built by Lockheed between February 1961 and August 1964. Similar to the corona satellite again, the film was brought to earth by reentry capsule. The mass of the satellite was, depending on version 1150-1500 kg. A total of 12 satellites were launched by Thor - Agena rocket, where there were at least 7 failures. The resolution of the satellite camera was only 140 m, it was used to create larger maps.

KH -6 Lanyard

KH -6, also called lanyard, was also produced by Lockheed and was used from March to July 1963. The resolution was 1.8 m, the film was brought back by re-entry capsule. There were three launches, one of which failed and another was a test satellite without film. Again came launchers of the type Thor Agena used. The aim of the KH- 6 program was to gain high resolution images.

KH -7 Gambit

KH -7 ( Gambit ) was built from July 1963 to June 1967 by General Electric. Unlike the previous satellites are information about that type still top secret. The resolution is probably 0.5 m, there were at least 38 satellite launches with Atlas - Agena rockets.

KH -8 Gambit

KH -8 ( also called Gambit ) was used from July 1966 to April 1984 and was developed by Lockheed (?) Built. The best resolution achieved was less than 0.1 m. The satellite remained in orbit longer than its predecessors; the pictures were taken back here with re-entry capsules, there were at least 55 satellite launches. Launcher was the Titan -3B Agena.

KH -9 Hexagon

KH -9 ( Hexagon, "Big Bird", built by Lockheed ) was used from June 1971 to April 1986. The mass of the satellite was about 11 to 13 tons, the resolution of the camera approximately 0.6 m. The film was returned with 4 re-entry capsule to Earth. There were 20 starts with titanium and titanium 3D 34D missiles. KH- 9 was developed parallel to KH-10/MOL as unmanned alternative.

KH -10 Dorian / MOL

KH -10 ( Dorian ) was a planned manned space station called the Manned Orbiting Laboratory ( MOL) - actually a manned spy satellite combined with a Gemini spacecraft. The project was abandoned after a flight test in 1969 before a working space station could be placed in orbit. Planned launch vehicle would have been the titanium -3M. After the adjustment of the program, developed in parallel KH -9 Hexagon satellite was transferred to the operational service.

KH -11 Kennan, later Crystal

KH -11 (Crystal, Kennan ) was built from December 1976 to November 1988, Lockheed and was the first deployable U.S. spy satellite that sent the pictures via radio. The satellite similar to the Hubble Space Telescope with a 2.3 -m mirror, the resolution was about 15 cm. At least nine satellites were launched with titanium and titanium 3D - 34D missile, the typical lifetime of a satellite was about 3 years.

KH -12 (?)

KH -12 ( Ikon (?), Improved Crystal) is essentially an improved variant of the KH -11 model and has a mirror with a diameter of 4.04 m. Another payload contains a variety of SIGINT systems and a laser rangefinder on board. The optical sensors working in the visible and infrared spectrum low in order to locate and identify heat sources and camouflaged or buried targets can. The CCD sensor used photoelectric cells based on gallium arsenide to achieve over the older silicon cells more resistant to laser - jamming measures, with this also comes a special laser- resistant coated lens for use. Full gas tank weighs the satellite up to 18 tons, which he carries about 5.3 tons of fuel. It is primarily designed by Lockheed Martin.

Since 1992, at least 5 satellites were launched, a sixth to have been started in the years 2007 or 2008. Neither the designation KH- 12 nor the code name Ikon have been officially confirmed. Launch vehicles were the Space Shuttle and Titan 4A rocket.

KH -13 (?)

KH -13 ( Misty ) is possibly the successor of KH- 12th Through its existence can only be speculated, possibly three satellites of this series in 1990 with a space shuttle, and 1999 and 2005 with Titan -4B launched missiles. The designation KH -13 is not officially confirmed. The terms 8X and ice ( Enhanced Imaging System) have also been mentioned in connection with that satellite.

Awards

2005 were James W. Plummer, Minoru S. Araki, Francis J. Madden, Edward A. Miller and Don H. Schoessler the Charles Stark Draper Prize for their participation in Corona.