KH-5 ARGON was a series of

reconnaissance satellite A reconnaissance satellite or intelligence satellite (commonly, although unofficially, referred to as a spy satellite) is an Earth observation satellite or communications satellite deployed for military or intelligence applications. The ...

s produced by the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

from February 1961 to August 1964. The KH-5 operated similarly to the

CORONA Corona (from the Latin for 'crown') most commonly refers to: * Stellar corona, the outer atmosphere of the Sun or another star * Corona (beer), a Mexican beer * Corona, informal term for the coronavirus SARS-CoV-2, which causes the COVID-19 di ...

series of satellites, as it ejected a canister of

photographic film Photographic film is a strip or sheet of transparent film base coated on one side with a gelatin photographic emulsion, emulsion containing microscopically small light-sensitive silver halide crystals. The sizes and other characteristics of th ...

. At least 12 missions were attempted, but at least 7 resulted in failure. The satellite was manufactured by Lockheed. Launches used

Thor-Agena Thor-Agena was a series of orbital launch vehicles. The launch vehicles used the Douglas-built Thor first stage and the Lockheed-built Agena second stages. They are thus cousins of the more-famous Thor-Deltas, which founded the Delta rocket ...

launch vehicles flying from

Vandenberg Air Force Base Vandenberg may refer to: * Vandenberg (surname), including a list of people with the name * USS General Harry Taylor (AP-145), USNS ''General Hoyt S. Vandenberg'' (T-AGM-10), transport ship in the United States Navy, sank as an artificial reef in K ...

, with the payload being integrated into the Agena.

Payload

Different versions of the satellite varied in

mass Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different elementar ...

from . At least two missions deployed ELINT subsatellites. Ground resolution for the satellite was , with a swath of . The onboard camera had a

focal length The focal length of an optical system is a measure of how strongly the system converges or diverges light; it is the inverse of the system's optical power. A positive focal length indicates that a system converges light, while a negative foca ...

of 76 mm. The purpose of the system, which produced relatively low-resolution images compared to other spy satellites, was to provide imagery for

cartography Cartography (; from grc, χάρτης , "papyrus, sheet of paper, map"; and , "write") is the study and practice of making and using maps. Combining science, aesthetics and technique, cartography builds on the premise that reality (or an im ...

purposes. This was one of the tasks that had originally been planned for the

SAMOS Samos (, also ; el, Σάμος ) is a Greek island in the eastern Aegean Sea, south of Chios, north of Patmos and the Dodecanese, and off the coast of western Turkey, from which it is separated by the -wide Mycale Strait. It is also a separate ...

series of satellites equipped with the (quickly cancelled) E-4 cameras. Each satellite took photographs for less than a week before returning its film. The satellite was in use during the same period as the KH-2 to KH-4A

and the

KH-6 LANYARD BYEMAN codenamed LANYARD, the KH-6 was the unsuccessful first attempt to develop and deploy a very high-resolution optical reconnaissance satellite by the United States National Reconnaissance Office. Launches and launch attempts spanned the per ...

satellites. Later satellites were the KH-4B and

KH-7 GAMBIT BYEMAN codenamed GAMBIT, the KH-7 (Air Force Program 206) was a reconnaissance satellite used by the United States from July 1963 to June 1967. Like the older CORONA system, it acquired imagery intelligence by taking photographs and returnin ...

. Images from three of the successful missions returned the first images of

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...

from space.

Satellites

Discoverer 20 (KH-5 9014A), was a USAF photographic reconnaissance satellite under the supervision of the

National Reconnaissance Office The National Reconnaissance Office (NRO) is a member of the United States Intelligence Community and an agency of the United States Department of Defense which designs, builds, launches, and operates the reconnaissance satellites of the U.S. f ...

(NRO). Discoverer 20 was the first KH-5 ARGON satellite to be launched. The launch occurred at 20:24:00 GMT on 17 February 1961. A Thor DM-21 Agena-B launch vehicle was used, flying from LC 75-3-4 at the Vandenberg Air Force Base. It was assigned the Harvard designation 1961 Epsilon 1. Discoverer 20 was operated in an Earth orbit, with a perigee of , an apogee of , 80.91° of inclination, and a period of 95.81 minutes. The satellite was equipped with a camera with a focal length of 76 mm, which had a resolution of . Images were recorded onto 127 mm film, and were to have been returned in a Satellite Recovery Vehicle (SRV) before the satellite ceased operations. The satellite weighed . Recovery of the capsule was not attempted due to a system malfunction, and thus the scientific experiment data obtained were limited. Discoverer 20 decayed on 28 July 1962.

Launches

References

* Mark Wade (August 9, 2003
KH-5
''Encyclopedia Astronautica''

GlobalSecurity.org {{US Reconnaissance Satellites Surveillance Reconnaissance satellites of the United States Military equipment introduced in the 1960s

Payload

Satellites

Launches

See also

References