Corona (satellite)

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The recovery of Discoverer 14 return capsule (typical for the CORONA series). Fairchild C-119J Flying Boxcar recovers CORONA Capsule 1960 USAF 040314-O-9999R-001.jpg
The recovery of Discoverer 14 return capsule (typical for the CORONA series).

The CORONA [1] program was a series of American strategic reconnaissance satellites produced and operated by the Central Intelligence Agency (CIA) Directorate of Science & Technology with substantial assistance from the U.S. Air Force. The CORONA satellites were used for photographic surveillance of the Soviet Union (USSR), China, and other areas beginning in June 1959 and ending in May 1972.

Contents

A KH-4B CORONA satellite. Kh-4b corona.jpg
A KH-4B CORONA satellite.
Discoverer 14 Launch 1960, Thor Agena "A" rocket Discoverer 14 Launch.jpg
Discoverer 14 Launch 1960, Thor Agena "A" rocket

Overview

Lockheed's covert "advanced projects" facility at Hiller Aircraft in Menlo Park, California. HillerAircraft AdvancedResearch.png
Lockheed's covert "advanced projects" facility at Hiller Aircraft in Menlo Park, California.

CORONA started under the name "Discoverer" as part of the WS-117L satellite reconnaissance and protection program of the U.S. Air Force in 1956. The WS-117L was based on recommendations and designs from the RAND Corporation. [2] The primary goal of the program was to develop a film-return photographic satellite to replace the U-2 spyplane in surveilling the Sino-Soviet Bloc, determining the disposition and speed of production of Soviet missiles and long-range bombers assets. The CORONA program was also used to produce maps and charts for the Department of Defense and other U.S. government mapping programs. [3]

The CORONA project was pushed forward rapidly following the shooting down of a U-2 spy plane over the Soviet Union on 1 May 1960. [4]

CORONA ultimately encompassed eight separate but overlapping series of satellites (dubbed "Keyhole" or KH [5] ), launched from 1959 to 1972. [6] :231 CORONA was complemented and ultimately succeeded by the higher resolution KH-7 Gambit and KH-8 Gambit 3 series of satellites. [7]

CORONA image of The Pentagon, 25 September 1967 Corona pentagon.jpg
CORONA image of The Pentagon, 25 September 1967

An alternative concurrent program to the CORONA program was SAMOS . That program included several types of satellite which used a different photographic method. This involved capturing an image on photographic film, developing the film aboard the satellite and then scanning the image electronically. The image was then transmitted via telemetry to ground stations. The Samos E-1 and Samos E-2 satellite programs used this system, but they were not able to take very many pictures and then relay them to the ground stations each day. Two later versions of the Samos program, such as the E-5 and the E-6, used the bucket-return approach pioneered with CORONA, but neither of the latter Samos series were successful. [8]

Spacecraft

The CORONA satellites were designated KH-1, KH-2, KH-3, KH-4, KH-4A and KH-4B. KH stood for "Key Hole" or "Keyhole" (Code number 1010), [5] with the name being an analogy to the act of spying into a person's room by peering through their door's keyhole. The incrementing number indicated changes in the surveillance instrumentation, such as the change from single-panoramic to double-panoramic cameras. The "KH" naming system was first used in 1962 with KH-4, the earlier numbers being applied retroactively. There were 144 CORONA satellites launched, of which 102 returned usable photographs.[ citation needed ]

Below is a list of CORONA launches, as compiled by the United States Geological Survey. [9] This table lists government's designation of each type of satellite (C, C-prime, J-1, etc.), the resolution of the camera, and a description of the camera system.

Time periodNo.NicknameResolutionNotesNumber
January 1959 – August 1960TestEngineering test flights5 systems; 1 recovery [10] [11]
June 1959 – September 1960KH-1"CORONA", C7.5 mFirst series of American imaging spy satellites. Each satellite carried a single panoramic camera and a single return vehicle.10 systems;
1 recovery
October 1960 – October 1961KH-2CORONA′, C′
(or "C-prime")*
7.5 mImproved single panoramic camera (affording differing obits) [6] :63–64 and a single return vehicle.10 systems;
6 recoveries
August 1961 – January 1962KH-3CORONA‴, C‴
(or "C-triple-prime")*
7.5 mSingle panoramic camera and a single return vehicle.6 systems;
5 recoveries
February 1962 – December 1963KH-4CORONA-M, Mural7.5 mFilm return. Two panoramic cameras.26 systems;
20 recoveries
August 1963 – October 1969KH-4ACORONA J-12.75 mFilm return with two reentry vehicles and two panoramic cameras. Large volume of imagery.52 systems;
94 recoveries
September 1967 – May 1972KH-4BCORONA J-31.8 mFilm return with two reentry vehicles and two panoramic rotator cameras17 systems;
32 recoveries
February 1961 – August 1964 KH-5 ARGON140 mLow-resolution mapping missions; single frame camera12 systems;
5 recoveries
March 1963 – July 1963 KH-6 LANYARD1.8 mExperimental camera in a short-lived program3 systems;
1 recovery [6] :231

*(The stray "quote marks" are part of the original designations of the first three generations of cameras.)

Program History

Discoverer

As American space launches were not classified until late 1961, [6] :176 [12] the first Corona satellites were cloaked with disinformation as being part of a space technology development program called Discoverer. To the public, Discoverer missions were scientific and engineering missions, the film-return capsules being used to return biological specimens. To facilitate this deception, several Corona capsules were built to house a monkey passenger. Many test monkeys were lost during ground tests of the capsule's life support system. [6] :50 The Discoverer cover proved to be cumbersome, inviting scrutiny from the scientific community. Discoverer 37, launched January 13, 1962, was the last Corona mission to bear the Discoverer name. Subsequent Corona missions were simply classified as "Department of Defense satellite launches." [13] :xiii–xiv

A CORONA Target (Y4-7) is located on the southeast corner of South Montgomery Road and West Corman Road in the City of Casa Grande, Arizona. Casa Grande-Corona Satellite Calibration Target-Montgomery-Corman-1.JPG
A CORONA Target (Y4-7) is located on the southeast corner of South Montgomery Road and West Corman Road in the City of Casa Grande, Arizona.

KH-1

The first series of Corona satellites were the Keyhole 1 (KH-1) satellites based on the Agena-A upper stage, which offered housing and an engine that provided attitude control in orbit. The KH-1 payload included the C (for CORONA) single panoramic camera built by Fairchild Camera and Instrument with a f/5.0 aperture and 61 cm (24 in) focal length. It had a ground resolution of 12.9 m (42 ft). Film was returned from orbit by a single General Electric Satellite Return Vehicle (SRV) constructed by General Electric. The SRV was equipped with a small onboard solid-fuel retro motor to deorbit the payload at the end of the mission. Recovery of the capsule was done in mid-air by a specially equipped aircraft. [14]

There were three camera-less test launches in the first half of 1959, none of them entirely successful. Discoverer 1 was a test vehicle carrying no SRV nor camera. Launched on 28 February 1959, it was the first man-made object put into a polar orbit, but only sporadically returned telemetry. Discoverer 2 (14 April 1959) carried a recovery capsule for the first time but no camera. The main bus performed well, but the capsule recovery failed, the SRV coming down over Spitzbergen rather than Hawaii. The capsule was never found. Discoverer 3 (3 June 1959), the first Discoverer to carry a biological package (four black mice in this case) failed to achieve orbit when its Agena crashed into the Pacific Ocean.

The pressure to orbit a photographic surveillance satellite to succeed the Lockheed U-2 was so great that operational, camera-equipped KH-1 launches began 25 June 1959 with the (unsuccessful) launching of Discoverer 4, despite there not having been a successful test of the life-support unit for biological passengers. This proved to be a moot point by this time as the link between the Discoverer series and living payloads had been established by the attempted flight of Discoverer 3. [6] :51–54

The three subsequent Discoverers were successfully orbited, but all of their cameras failed when the film snapped during loading. Ground tests determined that the acetate-based film became brittle in the vacuum of space, something that had not been discovered even in high altitude, low pressure testing. The Eastman Kodak Company was tasked with creating a more resilient replacement. Kodak developed a technique of coating a high-resolution emulsion on a type of polyester from DuPont. Not only was the resulting polyester-based film resistant to vacuum brittling, it weighed half as much as the prior acetate-based film. [6] :56

There were four more partially successful and unsuccessful missions in the KH-1 series before Discoverer 13 (10 August 1960), which managed a fully successful capsule recovery for the first time. This was the first recovery of a man-made object from space, beating the Soviet Korabl Sputnik 2 by nine days. Discoverer 13 is now on display in the "Milestones of Flight" hall in the National Air and Space Museum in Washington, D.C. The return capsule of the Discoverer 13 mission, which launched 10 August 1960, was successfully recovered the next day. [15] This was the first time that any object had been recovered successfully from orbit. After the mission of Discoverer 14, launched on 18 August 1960, its film bucket was successfully retrieved two days later by a Fairchild C-119 Flying Boxcar transport plane. This was the first successful return of a payload from orbit, occurring just one day before the launch of Korabl-Sputnik 2 a biosatellite that took into orbit the two Soviet space dogs, Belka and Strelka, and then safely returned them to the Earth. [16]

Discoverer 14 (18 August 1960) was the first fully successful CORONA mission. The cameras operated properly and the capsule was recovered from the Pacific Ocean 1.5 days after launch. [6] :38–39

The impact of CORONA on American intelligence gathering was tremendous. With the success of Discoverer 14, which returned 16 pounds of film and provided more coverage of the Soviet Union than all preceding U2 flights, for the first time the United States had a clear picture of the USSR's strategic nuclear capabilities. Before CORONA, the National Intelligence Estimates (NIE) of CIA were highly uncertain and strongly debated. Six months before Discoverer 14, an NIE predicted that the Soviets would have 140-200 ICBMs deployed by 1961. A month after the flight of Discoverer 14, that estimate was refined to just 10–25. [6] :38–39

Additionally, CORONA increased the pace at which intelligence could be received, with satellites providing monthly coverage from the start. Photographs were more easily assessed by analysts and political leaders than covert agent reports, improving not just the amount of intelligence but its accessibility. [6] :38–39

The KH-1 series ended with Discoverer 15 (13 September 1960), whose capsule successfully deorbited but sank into the Pacific Ocean and was not recovered. [17]

Later KH Series

In 1963, the KH-4 system was introduced with dual cameras and the program made completely secret, by the then president, Kennedy. The Discoverer label was dropped and all launches became classified. Because of the increased satellite mass, the basic Thor-Agena vehicle was enhanced by the addition of three Castor solid-fueled strap-on motors. On 28 February 1963, the first Thrust Augmented Thor lifted from Vandenberg Air Force Base at Launch Complex 75 carrying the first KH-4 satellite. The launch of the new and unproven booster went awry as one SRB failed to ignite. Eventually the dead weight of the strap-on motor dragged the Thor off its flight path, leading to a Range Safety destruct. It was suspected that a technician had not attached an umbilical on the SRB properly. Although some failures continued to occur during the next few years, the reliability rate of the program significantly improved with KH-4. [18] [19] Maneuvering rockets were also added to the satellite beginning in 1963. These were different from the attitude stabilizing thrusters which had been incorporated from the beginning of the program. Corona orbited in very low orbits to enhance resolution of its camera system. But at perigee (the lowest point in the orbit), Corona endured drag from the atmosphere of Earth. In time, this could cause its orbit to decay and force the satellite to re-enter the atmosphere prematurely. The new maneuvering rockets were designed to boost Corona into a higher orbit, and lengthen the mission time even if low perigees were used. [20] For use during unexpected crises, the National Reconnaissance Office (NRO) kept a Corona in "R-7" status, meaning ready for launch in seven days. By the summer of 1965, NRO was able to maintain Corona for launch within one day. [21]

Nine of the KH-4A and KH-4B missions included ELINT subsatellites, which were launched into a higher orbit. [22] [23]

At least two launches of Discoverer were used to test satellites for the Missile Defense Alarm System (MIDAS), an early missile-launch-detection program that used infrared cameras to detect the heat signature of rockets launching to orbit. [24]

The last launch under the Discoverer cover name was Discoverer 38 on 26 February 1962. Its bucket was successfully recovered in midair during the 65th orbit (the 13th recovery of a bucket; the ninth one in midair). [25] Following this last use of the Discoverer name, the remaining launches of Corona satellites were entirely TOP SECRET. The last Corona launch was on 25 May 1972. The project ended when Corona was replaced by the KH-9 Hexagon program. The best sequence of Corona missions was from 1966 to 1971, when there were 32 consecutive successful missions, including film recoveries.[ citation needed ]

Technology

The CORONA Satellite Index Camera Lens. Corona Satellite Index Camera Lens.jpg
The CORONA Satellite Index Camera Lens.

Cameras

The Corona satellites used special 70 mm film with a 24 in (610 mm) focal length camera. [26] Manufactured by Eastman Kodak, the film was initially 0.0003 in (7.6 μm) thick, with a resolution of 170 lines per mm (0.04 inch) of film. [27] [28] The contrast was 2-to-1. [27] (By comparison, the best aerial photography film produced in World War II could produce just 50 lines per mm (1250 per inch) of film). [27] The acetate-based film was later replaced with a polyester-based film stock that was more durable in Earth orbit. [29] The amount of film carried by the satellites varied over time. Initially, each satellite carried 8,000 ft (2,400 m) of film for each camera, for a total of 16,000 ft (4,900 m) of film. [27] But a reduction in the thickness of the film stock allowed more film to be carried. [29] In the fifth generation, the amount of film carried was doubled to 16,000 ft (4,900 m) of film for each camera for a total of 32,000 ft (9,800 m) of film. This was accomplished by a reduction in film thickness and with additional film capsules. [30] Most of the film shot was black and white. Infrared film was used on mission 1104, and color film on missions 1105 and 1008. Color film proved to have lower resolution, and so was never used again. [31]

The cameras were manufactured by the Itek Corporation. [32] A 12 in (30 cm), f/5 triplet lens was designed for the cameras. [33] Each lens was 7 in (18 cm) in diameter. [27] They were quite similar to the Tessar lenses developed in Germany by Carl Zeiss AG. [34] The cameras themselves were initially 5 ft (1.5 m) long, but later extended to 9 ft (2.7 m) in length. [35] Beginning with the KH-4 satellites, these lenses were replaced with Petzval f/3.5 lens. [31] The lenses were panoramic, and moved through a 70° arc perpendicular to the direction of the orbit. [27] A panoramic lens was chosen because it could obtain a wider image. Although the best resolution was only obtained in the center of the image, this could be overcome by having the camera sweep automatically ("reciprocate") back and forth across 70° of arc. [36] The lens on the camera was constantly rotating, to counteract the blurring effect of the satellite moving over the planet. [31]

A diagram of "J-1" type stereo/panoramic constantly rotating CORONA reconnaissance satellite camera system used on KH-4A missions from 1963 to 1969. Corona spysat camera system.jpg
A diagram of "J-1" type stereo/panoramic constantly rotating CORONA reconnaissance satellite camera system used on KH-4A missions from 1963 to 1969.

The first Corona satellites had a single camera, but a two-camera system was quickly implemented. [37] The front camera was tilted 15° aft, and the rear camera tilted 15° forward, so that a stereoscopic image could be obtained. [27] Later in the program, the satellite employed three cameras. [37] The third camera was employed to take "index" photographs of the objects being stereographically filmed. [38] The J-3 camera system, first deployed in 1967, placed the camera in a drum. This "rotator camera" (or drum) moved back and forth, eliminating the need to move the camera itself on a reciprocating mechanism. [39] The drum permitted the use of up to two filters and as many as four different exposure slits, greatly improving the variability of images that Corona could take. [40] The first cameras could resolve images on the ground down to 40 ft (12 m) in diameter. Improvements in the imaging system were rapid, and the KH-3 missions could see objects 10 ft (3.0 m) in diameter. Later missions would be able to resolve objects just 5 ft (1.5 m) in diameter. [41] A single mission was completed with a 1 ft (0.30 m) resolution but the limited field of view was determined to be detrimental to the mission.[ citation needed ]3 ft (0.91 m) resolution was found to be the optimum resolution for quality of image and field of view.

The initial Corona missions suffered from mysterious border fogging and bright streaks which appeared irregularly on the returned film. Eventually, a team of scientists and engineers from the project and from academia (among them Luis Alvarez, Sidney Beldner, Malvin Ruderman, Arthur Glines, [42] and Sidney Drell) determined that electrostatic discharges (called corona discharges) caused by some of the components of the cameras were exposing the film. [43] [44] Corrective measures included better grounding of the components, improved film rollers that did not generate static electricity, improved temperature controls, and a cleaner internal environment. [44] Although improvements were made to reduce the corona, the final solution was to load the film canisters with a full load of film and then feed the unexposed film through the camera onto the take-up reel with no exposure. This unexposed film was then processed and inspected for corona. If none was found or the corona observed was within acceptable levels, the canisters were certified for use and loaded with fresh film for a launch mission.

Calibration

Corona satellites were allegedly calibrated using the calibration targets located outside of Casa Grande, Arizona. The targets consisted of concrete arrows located in and to the south of the city, and may have helped to calibrate the cameras of the satellites. [45] [46] [47] These claims about the purpose of the targets, perpetuated by online forums and featured in National Geographic and NPR articles, have since been disputed, with aerial photogrammetry proposed as a more likely purpose for them. [48]

Recovery

A CORONA film recovery maneuver. CORONA film recovery maneuvar.jpg
A CORONA film recovery maneuver.
A CORONA film bucket payload. CORONA Recovery System Payload.png
A CORONA film bucket payload.

Film was retrieved from orbit via a reentry capsule (nicknamed "film bucket"), designed by General Electric, which separated from the satellite and fell to Earth. [49] After the fierce heat of reentry was over, the heat shield surrounding the vehicle was jettisoned at 60,000 ft (18 km) and parachutes deployed. [50] The capsule was intended to be caught in mid-air by a passing airplane [51] towing an airborne claw which would then winch it aboard, or it could land at sea. [52] A salt plug in the base would dissolve after two days, allowing the capsule to sink if it was not picked up by the United States Navy. [53] After Reuters reported on a reentry vehicle's accidental landing and discovery by Venezuelan farmers in mid-1964, capsules were no longer labeled "SECRET" but offered a reward in eight languages for their return to the United States. [54] Beginning with flight number 69, a two-capsule system was employed. [43] This also allowed the satellite to go into passive (or "zombie") mode, shutting down for as many as 21 days before taking images again. [30] Beginning in 1963, another improvement was "Lifeboat", a battery-powered system that allowed for ejection and recovery of the capsule in case power failed. [18] [55] The film was processed at Eastman Kodak's Hawkeye facility in Rochester, New York. [56]

The CORONA film bucket was later adapted for the KH-7 GAMBIT satellites, which took higher resolution photos.

Launch

CORONA were launched by a Thor-Agena rocket, which used a Thor first stage and an Agena as the second stage of the rocket lifting the CORONA into orbit.

The first satellites in the program orbited at altitudes 100 mi (160 km) above the surface of the Earth, although later missions orbited even lower at 75 mi (121 km). [31] Originally, CORONA satellites were designed to spin along their main axis so that the satellite would remain stable. Cameras would take photographs only when pointed at the Earth. The Itek camera company, however, proposed to stabilize the satellite along all three axes—keeping the cameras permanently pointed at the earth. [34] Beginning with the KH-3 version of the satellite, a horizon camera took images of several key stars. [38] A sensor used the satellite's side thruster rockets to align the rocket with these "index stars", so that it was correctly aligned with the Earth and the cameras pointed in the right direction. [57] Beginning in 1967, two horizon cameras were used. This system was known as the Dual Improved Stellar Index Camera (DISIC). [40]

Operations

The United States Air Force credits the Onizuka Air Force Station (then called Sunnyvale Air Force Station) as being the "birthplace of the CORONA program". [58] In May 1958, the Department of Defense directed the transfer of the WS-117L program to Advanced Research Projects Agency (ARPA). In FY1958, WS-117L was funded by the USAF at a level of US$108.2 million (inflation adjusted US$0.97 billion in 2021). For DISCOVERER, the Air Force and ARPA spent a combined sum of US$132.3 million in FY1959 (inflation adjusted US$1.17 billion in 2021) and US$101.2 million in FY1960 (inflation adjusted US$0.89 billion in 2021). [59] According to John N. McMahon, the total cost of the CORONA program amounted to $US850 million. [60]

The procurement and maintenance of the Corona satellites were managed by the Central Intelligence Agency (CIA), which used cover arrangements lasting from April 1958 to 1969 to get access to the Palo Alto plant of the Hiller Helicopter Corporation for the production. [61] At this facility, the rocket's second stage Agena, the cameras, film cassettes, and re-entry capsule were assembled and tested before shipment to Vandenberg Air Force Base. [62] In 1969, assembly duties were relocated to the Lockheed facilities in Sunnyvale, California. [63] (The NRO was worried that, as Corona was phased out, skilled technicians worried about their jobs would quit the program — leaving Corona without staff. The move to Sunnyvale ensured that enough skilled staff would be available.)

The decisions regarding what to photograph were made by the Corona Target Program. Corona satellites were placed into near-polar orbits. [41] This software, run by an on-board computer, was programmed to operate the cameras based on the intelligence targets to be imaged, the weather, the satellite's operational status, and what images the cameras had already captured. [64] Ground control for Corona satellites was initially conducted from Stanford Industrial Park, an industrial park on Page Mill Road in Palo Alto, California. It was later moved to Sunnyvale Air Force Base near Sunnyvale, California. [65]

Design staff

Minoru S. "Sam" Araki  [ de ], Francis J. Madden  [ de ], Edward A. Miller  [ de ], James W. Plummer, and Don H. Schoessler  [ de ] were responsible for the design, development, and operation of CORONA. For their role in creating the first space-based Earth photographic observation systems, they were awarded the Charles Stark Draper Prize in 2005. [66]

Declassification

The CORONA program was officially classified top secret until 1992. On 22 February 1995, the photos taken by the CORONA satellites, and also by two contemporary programs (Argon and KH-6 Lanyard) were declassified under an Executive Order signed by President Bill Clinton. [67] The further review by photo experts of the "obsolete broad-area film-return systems other than CORONA" mandated by President Clinton's order led to the declassification in 2002 of the photos from the KH-7 and the KH-9 low-resolution cameras. [68]

The declassified imagery has since been used by a team of scientists from the Australian National University to locate and explore ancient habitation sites, pottery factories, megalithic tombs, and Palaeolithic archaeological remains in northern Syria. [69] [70] Similarly, scientists at Harvard have used the imagery to identify prehistoric traveling routes in Mesopotamia. [71] [72]

The U.S. Geological Survey hosts more than 860,000 images of the Earth’s surface from between 1960 and 1972 from CORONA, ARGON, and LANYARD programs.

Launches

Mission No.Cover NameLaunch Date NSSDC ID No. Alt. NameCameraNotes
R&DDiscoverer Zero [73] 21 January 19591959-F01noneAgena ullage/separation rockets ignited on the pad while the launch vehicle was being fueled prior to the intended flight.
R&D Discoverer 1 28 February 1959 1959-002A 1959 Beta 1noneDecay: 17 March 1959. [74]
R&D Discoverer 2 13 April 1959 1959-003A 1959 GAMnoneFirst three-axis stabilized satellite; capsule recovery failed.
R&D Discoverer 3 3 June 1959 DISCOV3 1959-F02noneAgena guidance failure. Vehicle fell into the Pacific Ocean
9001 Discoverer 4 25 June 1959 DISC4 1959-U01KH-1Insufficient Agena engine thrust. Vehicle fell into the Pacific Ocean
9002 Discoverer 5 13 August 1959 1959-005A 1959 EPS 1KH-1Mission failed. Power supply failure. No recovery.
9003 Discoverer 6 19 August 1959 1959-006A 1959 ZETKH-1Mission failed. Retro rockets malfunctioned negating recovery.
9004 Discoverer 7 7 November 1959 1959-010A 1959 KAPKH-1Mission failed. Satellite tumbled in orbit.
9005 Discoverer 8 20 November 1959 1959-011A 1959 LAMKH-1Mission failed. Eccentric orbit negating recovery.
9006 Discoverer 9 4 February 1960 DiSC9 1960-F01KH-1Agena accidentally damaged during on-pad servicing. Premature cutoff and staging signal sent to Thor.
9007 Discoverer 10 19 February 1960 DISC10 1960-F02KH-1Control failure followed by RSO destruct T+52 seconds after launch
9008 Discoverer 11 15 April 1960 1960-004A 1960 DELKH-1Attitude control system malfunctioned. No film capsule recovery.
R&D Discoverer 12 29 June 1960 DISC12 1960-F08noneAgena attitude control malfunction. No orbit.
R&D Discoverer 13 10 August 1960 1960-008A 1960 THEnoneTested capsule recovery system; first successful capture.
9009 Discoverer 14 18 August 1960 1960-010A 1960 KAPKH-1First successful recovery of IMINT from space. Cameras operated satisfactorily.
9010 Discoverer 15 13 September 1960 1960-012A 1960 MUKH-1Mission failed. Attained orbit successfully. Capsule sank prior to retrieval.
9011 Discoverer 16 26 October 1960 1960-F15 1960-F15KH-2Agena failed to separate from Thor.
9012 Discoverer 17 12 November 1960 1960-015A 1960 OMIKH-2Mission failed. Obtained orbit successfully. Film separated before any camera operation leaving only 1.7 ft (0.52 m) of film in capsule.
9013 Discoverer 18 7 December 1960 1960-018A 1960 SIGKH-2First successful mission employing KH-2 camera system.
RM-1 Discoverer 19 20 December 1960 1960-019A 1960 TAUnoneTest of Missile Defense Alarm System
9014A Discoverer 20 17 February 1961 1961-005A 1961 EPS 1KH-5See KH-5
RM-2 Discoverer 21 18 February 1961 1961-006A 1961 ZETnoneTest of restartable rocket engine
9015 Discoverer 22 30 March 1961 DISC22 1961-F02KH-2Agena control malfunction. No orbit.
9016A Discoverer 23 8 April 1961 1961-011A 1961 LAM 1KH-5See KH-5
9018A Discoverer 24 8 June 1961 DISC24 1961-F05KH-5See KH-5
9017 Discoverer 25 16 June 1961 1961-014A 1961 XI 1KH-2Capsule recovered from water on orbit 32. Streaks throughout film.
9019 Discoverer 26 7 July 1961 1961-016A 1961 PIKH-2Main camera malfunctioned on pass 22.
9020A Discoverer 27 21 July 1961 DISC27 1961-F07KH-5See KH-5
9021 Discoverer 28 4 August 1961 DISC28 1961-F08KH-2Thor guidance failure. RSO destruct at T+60 seconds.
9022 Discoverer 30 12 September 1961 1961-024A 1961 OME 1KH-3Best mission to date. Same out-of-focus condition as in 9023.
9023 Discoverer 29 30 August 1961 1961-023A 1961 PSIKH-3First use of KH-3 camera system. All frames out of focus.
9024 Discoverer 31 17 September 1961 1961-026A 1961 A BETKH-3Mission failed. Power failure and loss of control gas on orbit 33. Capsule was not recovered.
9025 Discoverer 32 13 October 1961 1961-027A 1961 A GAM 1KH-3Capsule recovered on orbit 18. 96% of film out of focus.
9026 Discoverer 33 23 October 1961 DISC33 1961-F10KH-3Mission failed. Satellite failed to separate from Thor booster. No orbit.
9027 Discoverer 34 5 November 1961 1961-029A 1961 A EPS 1KH-3Mission failed. Improper launch angle resulted in extreme orbit. Gas valve failed
9028 Discoverer 35 15 November 1961 1961-030A 1961 A ZET 1KH-3All cameras operated satisfactorily. Grainy emulsion noted.
9029 Discoverer 36 12 December 1961 1961-034A 1961 A KAP 1KH-3Best mission to date. Launch carried OSCAR 1 to orbit.
9030 Discoverer 37 13 January 1962 DISC37 1962-F01KH-3Mission failed. No orbit.
9031Discoverer 3827 February 1962 1962-005A 1962 EPS 1KH-4First mission of the KH-4 series. Much of film slightly out of focus.
90321962 Lambda 118 April 1962 1962-011A 1962 LAM 1KH-4Best mission to date.
9033FTV 112528 April 1962 1962-017A 1962 RHO 1KH-4Mission failed. Parachute ejector squibs holding parachute container cover failed to fire. No recovery.
9034A FTV 112615 May 1962 1962-018A 1962 SIG 1KH-5See KH-5
9035FTV 112830 May 1962 1962-021A 1962 PHI 1KH-4Slight corona static on film.
9036FTV 11272 June 1962 1962-022A 1962 CHI 1KH-4Mission failed. During air catch. Launch carried OSCAR 2 to orbit.
9037FTV 112923 June 1962 1962-026A 1962 A BETKH-4Corona static occurs on some film.
9038FTV 115128 June 1962 1962-027A 1962 A GAMKH-4Severe corona static.
9039FTV 113021 July 1962 1962-031A 1962 A ETAKH-4Aborted after 6 photo passes. Heavy corona and radiation fog.
9040FTV 113128 July 1962 1962-032A 1962 A THEKH-4No filters on slave horizon cameras. Heavy corona and radiation fog.
9041FTV 11522 August 1962 1962-034A 1962 A KAP 1KH-4Severe corona and radiation fog.
9042A FTV 11321 September 1962 1962-044A 1962 A UPSKH-5See KH-5
9043FTV 113317 September 1962 1962-046A 1962 A CHIKH-4placed in highly eccentric orbit (207 x 670 km), capsule called down after one day, film suffered severe radiation fog due to South Atlantic Anomaly crossing [75] [76] [77]
9044FTV 115329 August 1962 1962-042A 1962 A SIGKH-4Erratic vehicle attitude. Radiation fog minimal.
9045FTV 115429 September 1962 1962-050A 1962 B BETKH-4First use of stellar camera
9046A FTV 11349 October 1962 1962-053A 1962 B EPSKH-5See KH-5
9047FTV 11365 November 1962 1962-063A 1962 B OMIKH-4Camera door malfunctioned
9048FTV 113524 November 1962 1962-065A 1962 B RHOKH-4Some film exposed through base.
9049FTV 11554 December 1962 1962-066A 1962 B SIGKH-4Mission failed. During air catch chute tore
9050FTV 115614 December 1962 1962-069A 1962 B PHIKH-4Best mission to date.
9051OPS 00487 January 1963 1963-002A 1963-002AKH-4Erratic vehicle attitude. Frame ephemeris not created.
9052OPS 058328 Feb 1963 1963-F02 1963-F02KH-4Mission failed. Destroyed by range safety officer
9053OPS 07201 Apr 1963 1963-007A 1963-007AKH-4Best imagery to date.
9054OPS 095412 Jun 1963 1963-019A 1963-019AKH-4Some imagery seriously affected by corona.
9055A OPS 100826 Apr 1963 1963-F07 1963-F07KH-5See KH-5
9056OPS 099926 Jun 1963 1963-025A 1963-025AKH-4Experimental camera carried. Film affected by light leaks.
9057OPS 126619 Jul 1963 1963-029A 1963-029AKH-4Best mission to date.
9058A OPS 156129 Aug 1963 1963-035A 1963-035AKH-5See KH-5
9059A OPS 243729 Oct 1963 1963-042A 1963-042AKH-5See KH-5
9060OPS 22689 Nov 1963 1963-F14 1963-F14KH-4Mission failed. No orbit.
9061OPS 226027 Nov 1963 1963-048A 1963-048AKH-4Mission failed. Return capsule separated from satellite but remained in orbit.
9062OPS 138821 Dec 1963 1963-055A 1963-055AKH-4Corona static fogged much of film.
9065A OPS 273921 Aug 1964 1964-048A 1964-048AKH-5See KH-5
9066A OPS 323613 Jun 1964 1964-030A 1964-030AKH-5See KH-5
1001OPS 141924 Aug 1963 1963-034A 1963-034AKH-4AFirst mission of KH-4A. Some film was fogged. Two buckets but 1001-2 was never recovered.
1002OPS 135323 Sep 1963 1963-037A 1963-037AKH-4ASevere light leaks
1003OPS 346724 Mar 1964 1964-F04 1964-F04KH-4AMission failed. Guidance system failed. No orbit.
1004OPS 344415 Feb 1964 1964-008A 1964-008AKH-4AMain cameras operated satisfactorily. Minor degradations due to static and light leaks.
1005OPS 292127 Apr 1964 1964-022A 1964-022AKH-4AMission failed. Recovery vehicle impacted in Venezuela.
1006OPS 34834 Jun 1964 1964-027A 1964-027AKH-4AHighest quality imagery attained to date from the KH-4 system.
1007OPS 375419 Jun 1964 1964-032A 1964-032AKH-4AOut-of-focus area on some film.
1008OPS 349110 Jun 1964 1964-037A 1964-037AKH-4ACameras operated satisfactorily
1009OPS 30425 Aug 1964 1964-043A 1964-043AKH-4ACameras operated successfully.
1010OPS 349714 Sep 1964 1964-056A 1964-056AKH-4ASmall out of focus areas on both cameras at random times throughout the mission.
1011OPS 33335 Oct 1964 1964-061A 1964-061AKH-4APrimary mode of recovery failed on second portion of the mission (1011-2). Small out of focus areas present at random on both cameras.
1012OPS 355917 Oct 1964 1964-067A 1964-067AKH-4AVehicle attitude became erratic on the second portion of the mission necessitating an early recovery.
1013OPS 54342 Nov 1964 1964-071A 1964-071AKH-4AProgram anomaly occurred immediately after launch when both cameras operated for 417 frames. Main cameras ceased operation on rev 52D of first portion of mission negating second portion. About 65% of aft camera film is out of focus.
1014OPS 336018 Nov 1964 1964-075A 1964-075AKH-4ACameras operated successfully.
1015OPS 335819 Dec 1964 1964-085A 1964-085AKH-4ADiscrepancies in planned and actual coverage due to telemetry problems during the first 6 revolutions. Small out-of-focus areas on film from aft camera.
1016OPS 392815 Jan 1965 1965-002A 1965-002AKH-4ASmearing of highly reflective images due to reflections within camera.
1017OPS 478225 Feb 1965 1965-013A 1965-013AKH-4ACapping shutter malfunction occurred during last 5 passes of mission.
1018OPS 480325 Mar 1965 1965-026A 1965-026AKH-4ACameras operated successfully. First KH-4A reconnaissance system to be launched into a retrograde orbit.
1019OPS 502329 Apr 1965 1965-033A 1965-033AKH-4ACameras operated successfully. Malfunction in recovery mode on 1019-2 negated recovery.
1020OPS 84259 Jun 1965 1965-045A 1965-045AKH-4AAll cameras operated satisfactorily. Erratic attitude caused an early recovery after the second day of 1020–2.
1021OPS 843118 May 1965 1965-037A 1965-037AKH-4AAft camera ceased operation on pass 102.
1022OPS 554319 Jun 1965 1965-057A 1965-057AKH-4AAll cameras operated satisfactorily.
1023OPS 720817 Aug 1965 1965-067A 1965-067AKH-4AProgram anomaly caused the fore camera to cease operation during revolutions 103–132.
1024OPS 722122 Sep 1965 1965-074A 1965-074AKH-4AAll cameras operated satisfactorily. Cameras not operated on passes 88D-93D.
1025OPS 532505 Oct 1965 1965-079A 1965-079AKH-4AMain cameras operated satisfactorily.
1026OPS 215528 Oct 1965 1965-086A 1965-086AKH-4AAll cameras operated satisfactorily.
1027OPS 724909 Dec 1965 1965-102A 1965-102AKH-4AErratic attitude necessitated recovery after two days of operation. All cameras operated satisfactorily.
1028OPS 463924 Dec 1965 1965-110A 1965-110AKH-4ACameras operated satisfactorily.
1029OPS 72912 Feb 1966 1966-007A 1966-007AKH-4ABoth panoramic cameras were operational throughout.
1030OPS 34889 Mar 1966 1966-018A 1966-018AKH-4AAll cameras operated satisfactorily.
1031OPS 16127 Apr 1966 1966-029A 1966-029AKH-4AThe aft-looking camera malfunctioned after the recovery of bucket 1. No material was received in bucket 2 (1031-2).
1032OPS 15083 May 1966 1966-F05A 1966-F05KH-4AMission failed. Vehicle failed to achieve orbit.
1033OPS 177824 May 1966 1966-042A 1966-042AKH-4AThe stellar camera shutter of bucket 2 remained open for approximately 200 frames.
1034OPS 159921 Jun 1966 1966-055A 1966-055AKH-4AFailure of velocity altitude programmer produced poor imagery after revolution 5.
1035OPS 170320 Sep 1966 1966-085A 1966-085AKH-4AAll cameras operated satisfactorily. First mission flown with pan geometry modification.
1036OPS 15459 Aug 1966 1966-072A 1966-072AKH-4AAll cameras operated satisfactorily.
1037OPS 18668 Nov 1966 1966-102A 1966-102AKH-4ASecond pan geometry mission. Higher than normal base plus fog encountered on both main camera records.
1038OPS 166414 Jan 1967 1967-002A 1967-002AKH-4AFair image quality.
1039OPS 475022 Feb 1967 1967-015A 1967-015AKH-4ANormal KH-4 mission. Light from horizon camera on both main camera records during 1039–1.
1040OPS 477930 Mar 1967 1967-029A 1967-029AKH-4ASatellite flown nose first.
1041OPS 46969 May 1967 1967-043A 1967-043AKH-4ADue to the failure of the booster cut-off switch, the satellite went into a highly eccentric orbit. There was significant image degradation.
1042OPS 355916 Jun 1967 1967-062A 1967-062AKH-4ASmall out-of-focus area in forward camera of 1042–1.
1043OPS 48277 Aug 1967 1967-076A 1967-076AKH-4AForward camera film came out of the rails on pass 230D. Film degraded past this point.
1044OPS 05622 Nov 1967 1967-109A 1967-109AKH-4AAll cameras operated fine.
1045OPS 224324 Jan 1968 1968-008A 1968-008AKH-4AAll cameras operated satisfactorily.
1046OPS 484914 Mar 1968 1968-020A 1968-020AKH-4AImage quality good for 1046-1 and fair for 1046–2.
1047OPS 534320 Jun 1968 1968-052A 1968-052AKH-4AOut-of-focus imagery is present on both main camera records.
1048OPS 016518 Sep 1968 1968-078A 1968-078AKH-4AFilm in the forward camera separated and camera failed on mission 1048-2
1049OPS 474012 Dec 1968 1968-112A 1968-112AKH-4ADegraded film
1050OPS 372219 Mar 1969 1969-026A 1969-026AKH-4ADue to abnormal rotational rates after revolution 22
1051OPS 11012 May 1969 1969-041A 1969-041AKH-4AImagery of both pan camera records is soft and lacks crispness and edge sharpness.
1052OPS 353122 Sep 1969 1969-079A 1969-079AKH-4ALast of the KH-4A missions
1101OPS 508915 Sep 1967 1967-087A 1967-087AKH-4BFirst mission of the KH-4B series. Best film to date.
1102OPS 100109 Dec 1967 1967-122A 1967-122AKH-4BNoticeable image smear for forward camera
1103OPS 14191 May 1968 1968-039A 1968-039BKH-4BOut-of-focus imagery is present on both main camera records.
1104OPS 59557 Aug 1968 1968-065A 1968-065AKH-4BBest imagery to date on any KH-4 systems. Bicolor and color infrared experiments were conducted on this mission, including SO-180 IR camouflage detection film. [78]
1105OPS 13153 Nov 1968 1968-098A 1968-098AKH-4BImage quality is variable and displays areas of soft focus and image smear.
1106OPS 38905 Feb 1969 1969-010A 1969-010AKH-4BThe best image quality to date.
1107OPS 365424 Jul 1969 1969-063A 1969-063AKH-4BForward camera failed on pass 1 and remained inoperative throughout the rest of the mission.
1108OPS 66174 December 1969 1969-105A 1969-105AKH-4BCameras operated satisfactorily and the mission carried 811 ft (247 m) of aerial color film added to the end of the film supply.
1109OPS 04404 March 1970 1970-016A 1970-016AKH-4BCameras operated satisfactorily but the overall image quality of both the forward and aft records is variable.
1110OPS 472020 May 1970 1970-040A 1970-040AKH-4BThe overall image quality is less than that provided by recent missions and 2
1111OPS 432423 June 1970 1970-054A 1970-054AKH-4BThe overall image quality is good.
1112OPS 499218 November 1970 1970-098A 1970-098AKH-4BThe forward camera failed on pass 104 and remained inoperative throughout the rest of the mission.
1113OPS 329717 February 1971 1971-F01A 1971-F01KH-4BMission failed due to failure of Thor booster. Destroyed shortly after launch.
1114OPS 530024 March 1971 1971-022A 1971-022AKH-4BThe overall image quality is good and comparable to the best of past missions. On-board program failed after pass 235
1115OPS 545410 September 1971 1971-076A 1971-076AKH-4BOverall image quality is good.
1116OPS 564019 April 1972 1972-032A 1972-032AKH-4BVery successful mission and image quality was good.
1117OPS 637125 May 1972 1972-039A 1972-039AKH-4BLast KH-4B mission. Very successful mission, failure to deploy one solar panel and leak in Agena gas system shortened mission from 19 to 6 days [77]

The 1963 thriller novel Ice Station Zebra and its 1968 film adaptation were inspired, in part, by news accounts from April 17, 1959, about a missing experimental Corona satellite capsule (Discoverer 2) that inadvertently landed near Spitzbergen on April 13. While Soviet agents may have recovered the vehicle, [62] [79] it is more likely that the capsule landed in water and sank. [54]

See also

Related Research Articles

KH-5 Argon

KH-5 ARGON was a series of reconnaissance satellites produced by the United States from February 1961 to August 1964. The KH-5 operated similarly to the Corona series of satellites, as it ejected a canister of photographic film. At least 12 missions were attempted, but at least 7 resulted in failure. The satellite was manufactured by Lockheed. Launches used Thor-Agena rockets flying from Vandenberg Air Force Base, with the payload being integrated into the Agena.

KH-7 Gambit

BYEMAN codenamed GAMBIT, the KH-7 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 returning the undeveloped film to earth. It achieved a typical ground-resolution of 2 ft (0.61 m) to 3 ft (0.91 m). Though most of the imagery from the KH-7 satellites was declassified in 2002, details of the satellite program remained classified until 2011.

Samos (satellite)

The SAMOS or SAMOS-E program was a relatively short-lived series of reconnaissance satellites for the United States in the early 1960s, also used as a cover for the initial development of the KH-7 GAMBIT system. Reconnaissance was performed with film cameras and television surveillance from polar low Earth orbits with film canister returns and transmittals over the United States. SAMOS was first launched in 1960 from Vandenberg Air Force Base.

KH-9 Hexagon American family of spy satellites

KH-9, commonly known as Big Bird or KeyHole-9, was a series of photographic reconnaissance satellites launched by the United States between 1971 and 1986. Of twenty launch attempts by the National Reconnaissance Office, all but one were successful. Photographic film aboard the KH-9 was sent back to Earth in recoverable film return capsules for processing and interpretation. The best ground resolution achieved by the main cameras was better than 0.6 m.

Discoverer 1 American reconnaissance satellite launched in 1959; failed to achieve orbit

Discoverer 1 was the first of a series of satellites which were part of the CORONA reconnaissance satellite program. It was launched on a Thor-Agena A rocket on 28 February 1959 at 21:49:16 GMT from Vandenberg Air Force Base in California. It was a prototype of the KH-1 satellite, but did not contain either a camera or a film capsule. It was the first satellite launched toward the South Pole in an attempt to achieved a polar orbit, but was unsuccessful. A CIA report, later declassified, concluded that "Today, most people believe the Discoverer 1 landed somewhere near the South Pole".

Discoverer 14 Reconnaissance satellite

Discoverer 14, also known as Corona 9009, was a spy satellite used in the Corona program managed by Advanced Research Projects Agency (ARPA) of the Department of Defense and the United States Air Force. On 19 August 1960, usable photographic film images of the Soviet Union taken by the satellite were recovered by a C-119 recovery aircraft. This was the first successful recovery of film from an orbiting satellite and the first mid-air recovery of an object returning from Earth orbit.

Discoverer 13 Reconnaissance satellite

Discoverer 13 was an American optical reconnaissance satellite launched on 10 Aug 1960 at 20:37:54 GMT. The last of five test flights of the Corona KH-1 spy satellite series, it was the first fully successful flight in the Discoverer series. On 11 Aug, after 17 orbits, the satellite's reentry capsule was recovered in the Pacific Ocean by the Haiti Victory. Its payload, an American flag, was presented to President Eisenhower four days later.

Discoverer 11 Reconnaissance satellite

Discoverer 11, also known as Corona 9008, was an American optical reconnaissance satellite launched on 15 Apr 1960 at 20:30:37 GMT. The eighth of ten operational flights of the Corona KH-1 spy satellite series, it successfully employed the first space-worthy camera film; however, Discoverer's film return capsule was lost during reentry on 16 Apr when the satellite's spin motors exploded.

Discoverer 18 Reconnaissance satellite

Discoverer 18, also known as Corona 9013, was an American optical reconnaissance satellite launched on 7 December 1960 at 20:24:00 GMT. It was the first successful, and the third of ten total Corona KH-2 satellites, based on the Agena-B.

Discoverer 4 Reconnaissance satellite

Discoverer 4, also known as Corona 9001, was an American optical reconnaissance satellite launched on 25 Jun 1959 at 22:47:45 GMT, the first of ten operational flights of the Corona KH-1 spy satellite series, and the first satellite to be equipped for photo surveillance. The satellite was not successfully orbited. Its loss spurred improvements of its rocket booster to ensure the success of subsequent missions.

Discoverer 9 Reconnaissance satellite

Discoverer 9, also known as Corona 9006, was an American optical reconnaissance satellite launched on 4 Feb 1960 at 18:51:45 GMT, the sixth of ten operational flights of the Corona KH-1 spy satellite series, and the first of them to be equipped with a new, vacuum-proof, polyester-based film. The satellite was not successfully orbited.

Discoverer 10 Reconnaissance satellite

Discoverer 10, also known as Corona 9007, was an American optical reconnaissance satellite launched on 19 Feb 1960 at 20:15:14 GMT, the seventh of ten operational flights of the Corona KH-1 spy satellite series,

Discoverer 3 Reconnaissance satellite

Discoverer 3 was an American optical reconnaissance satellite launched on 3 June 1959 at 20:09:20 GMT, the third of three test flights of the Corona KH-1 spy satellite series. The first Discoverer mission to carry live animal passengers, Discoverer 3 was lost when its carrying Agena-A booster crashed into the Pacific Ocean.

Discoverer 5 Reconnaissance satellite

Discoverer 5, also known as Corona 9002, was an American optical reconnaissance satellite launched on 13 August 1959 at 19:00:08 GMT, the second of ten operational flights of the Corona KH-1 spy satellite series. Though the satellite was successfully orbited, the onboard camera failed within the first orbit, and the film-return capsule failed to deorbit.

Discoverer 6 Reconnaissance satellite

Discoverer 6, also known as Corona 9003, was an American optical reconnaissance satellite launched on 19 August 1959 at 19:24:44 GMT, the third of ten operational flights of the Corona KH-1 spy satellite series. Though the spacecraft was orbited successfully, the onboard camera ceased operating by the second orbit, and the film-return capsule could not be recovered.

Discoverer 7 Reconnaissance satellite

Discoverer 7, also known as Corona 9004, was an American optical reconnaissance satellite launched on 7 November 1959 at 20:28:41 GMT, the fourth of ten operational flights of the Corona KH-1 spy satellite series. Though the satellite was orbited successfully, its film capsule failed to separate from the main satellite.

Discoverer 8 Reconnaissance satellite

Discoverer 8, also known as Corona 9005, was an American optical reconnaissance satellite launched on 20 November 1959 at 19:25:24 GMT, the fifth of ten operational flights of the Corona KH-1 spy satellite series. Overburn by the carrier rocket placed the satellite in a higher apogee, more eccentric orbit than planned, the camera failed to operate, and the film return capsule was lost on reentry after separation from the main satellite on 21 November.

Discoverer 12 Reconnaissance satellite

Discoverer 12 was an American optical reconnaissance satellite launched on 29 Jun 1960 at 22:00:44 GMT. The fourth of five test flights of the Corona KH-1 spy satellite series, it was lost when the second stage failed during launch.

Discoverer 15 Reconnaissance satellite

Discoverer 15, also known as Corona 9010, was a spy satellite used in the Corona program managed by Advanced Research Projects Agency (ARPA) of the Department of Defense and the United States Air Force. Launched on 13 September 1960, the satellite took reconnaissance photos of the Soviet Union. However, its recoverable film capsule was lost in the Pacific Ocean after reentry outside the recovery zone on 15 September.

References

Notes

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  4. United States; Central Intelligence Agency; Ruffner, Kevin Conley; Center for the Study of Intelligence (U.S.); History Staff (1 January 1995). Corona America's first satellite program. Washington, D.C.: History Staff, Center for the Study of Intelligence, Central Intelligence Agency. pp. xiii. OCLC   42006243.PD-icon.svgThis article incorporates text from this source, which is in the public domain.
  5. 1 2 Yenne, Bill (1985). The Encyclopedia of US Spacecraft. Exeter Books (A Bison Book), New York. ISBN   978-0-671-07580-4. p.82 Key Hole
  6. 1 2 3 4 5 6 7 8 9 10 Day, Dwayne A.; Logsdon, John M.; Latell, Brian (1998). Eye in the Sky: The Story of the Corona Spy Satellites. Washington and London: Smithsonian Institution Press. ISBN   1-56098-830-4. OCLC   36783934.
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  30. 1 2 Peebles, p. 157
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  32. Yenne, p. 64
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  37. 1 2 Ruffner, p. 37
  38. 1 2 Kramer, p. 354
  39. Ruffner, p. 34, 36
  40. 1 2 Ruffner, p. 36
  41. 1 2 Chun, p. 75
  42. personal memoirs of Arthur R Glines, Corona program engineer, 1/1962 to 6/1967
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  44. 1 2 Drell, "Reminiscences of Work on National Reconnaissance", p. 42
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  50. Collins, p. 108
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  55. Peebles, p. 159
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  61. Peebles, p. 51
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  66. Executive Order 12951
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