One of the most important contributions of the space program has been imaging. This technology has contributed to weather forecasting, natural resources conservation, prospecting and a multitude of business and public interest applications. Imaging from space started with the military and the need to spy on our cold war adversaries, primarily with regard to nuclear capabilities. With the end of the cold war, imaging is still important to determine the spread of weapons of mass destruction, including chemical and biological. It also plays a role in combat reconnaissance, as witnessed in the Gulf War.

The Military developed imaging technology that went on to have significant civilian applications. Today, the military still enjoys the best technology, but space images for civilian use are of high quality, including images from French and Russian sources. This technology began with a Defense Department program called Corona.

Corona was the first operational space imaging reconnaissance satellite program, approved in February, 1958. Its' goal was to take pictures from space of the Soviet Bloc countries and return the photographic film for processing and analysis. In the 1950's, it became increasingly difficulty to obtain intelligence data about soviet military capabilities, especially nuclear. Balloons carrying cameras(Genetrix) at high altitude were tried starting on January 22, 1956 but were not reliable. High altitude U-2 spy planes were used to gather intelligence, starting July 4, 1956, but were discontinued when Francis Gary Powers was shot down by a Soviet SAM May 1, 1960. Outer space became the ultimate 'high ground'.

Corona camera systems were integrated into an Agena upper stage and launched into Polar orbit by Thor booster from Van den Berg AFB, CA. Corona used an innovative constant rotating panoramic camera system, which provided a stable platform which was constantly pointed toward the Earth. The basic camera technology was a breakthrough developed as part of the Genetrix Project. Film was loaded into a recovery vehicle and returned to Earth for air recovery by USAF C-119 aircraft, while floating to Earth on a parachute. Sea recovery was used as a backup.

Corona was developed in secrecy so that targeted nations would not know what was planned. Even the existence of Corona was not acknowledged. The Corona project management structure became the National Reconnaissance Office(NRO). NRO is a supersecret agency whose exist was not even acknowledged until recently. On December 23, 1958, the government created an project, called Discoverer, with an acknowledged goal of scientific research: testing of returning vehicles to Earth for the recovery of occupants, instruments, films and other scientific payloads; development of an early warning system for the detection of enemy missiles; development of a stable platform for scientific observations. The entire Discoverer Project was a ruse. No scientific objectives were planned. Discoverer actually had a staff working on scientific instruments, including launching pods for space mice, but none were ever launched or intended to be launched. Discoverer Project staff did not know about Corona. The cover was so elaborate that scientific instruments placed on Discoverer satellites were removed before launch. Although Corona developed recovery techniques, these were never intended as research for manned space programs. The Discoverer program was publicly classified after the launch of Discoverer XXXVIII, December 12, 1961. Those involved in Discoverer went on to other projects.

We know about Corona today, because President Clinton signed an executive order on February 24, 1995, releasing more than 800,000 images of the Earth taken by the project. These will be available to the public via the National Archives and Records Administration and the USGS EROS DATA Center. NRO now has a website, and data on Corona and Corona images are on that site. Current Landsat archives provide a photo record back to 1972. These images will add coverage for the period 1960-1972, and give those studying environmental developments an extra decade of data. These images are generally consistent with Landsat data. The resolution of the first systems(KH-1) was 40'. Each model improved resolution, ultimately reaching 6 feet, with the KH-4B(stereo image). Individual pictures usually cover an area 10 x 120 miles. Additional Corona memorabilia has been donated to the National Air & Space Museum.

Efforts have been made to acknowledge the scientific breakthroughs brought forth in the Corona Program:

First photoreconnaissance satellite

First recovery of a object from space(recovery vehicle in the Smithsonian)

First mid-air recovery of a vehicle returning from space

Quantum advancements in photoimaging from space

First mapping of earth from space

First stereo-optical data from space

First multiple reentry vehicles from space

Corona made todays high resolution imaging possible. The people working on this project were honored at a May 24, 1995 ceremony at the National Air & Space Museum. A book has also been published, Corona Between the Sun & the Earth: The First NRO Reconnaissance Eye in Space, by the American Society for Photogrammetry and Remote Sensing, April 7, 1997.

There were three diagnostic flights to test the Thor-Agena systems. These were designated Discoverer I, II and III. These were related to, but not part of the Corona series. Discover I has long been thought to be the first successful polar orbit. Data released from Corona suggests that Discoverer I did not actually achieve orbit. It was reported as a success by the military based on successful initiation of second stage burn. Orbital insertion was never confirmed by telemetry. The first polar orbit was probably Discoverer II.

Corona started with mission 9001, June 25, 1959, which failed to orbit. This was publicly called Discoverer IV. The early history of Corona is replete with hardware failures. Mission 9002(8/13/59) was the first to achieve orbit, but the camera failed. The camera also failed on 9003 and 9005. Missions 9004-6-7 failed to orbit. The camera worked for the first time on mission 9008, but the RV was not recoverable. A combination of extraordinary corrective action and two diagnostic flights brought success with the first photos from mission 9009. The first corona image was a soviet bomber base at Mys Schmidta in the far east, only 400 miles from Nome, AK. By mid-1961, Corona would supply a constant stream of intelligence data. Early Corona missions lasted one day. Later missions could take sufficient film and power supplies to last 19 days. A complete list of Corona missions follows this article.

The intelligence community used two sets of terminology for the Corona series. The Air Force and CIA - program managers - used program and launch designations. Those using the Photoreconnaissance('spy photos') referred to the camera systems, Keyhole or KH. Corona missions were numbered according to camera systems. These are listed below:

Series Camera Designations Remarks

90 KH-1 - KH-4

90 "A" KH-5 ARGON missions

80 KH-6 LANYARD missions

10 KH-4A

11 KH-4B

The initial camera systems were manufactured by Fairchild Camera Co. KH-1 had a resolution of 40'. This would be easy to fool if the enemy knew its' capability, so improvement was necessary. KH-2 improved the image motion compensation system and the film(all film was the product of Kodak) to gain 25' resolution.

Itek Corporation produced all subsequent cameras. The KH-3 was an upgrade of the earlier models, incorporating a faster lens, which allowed finer grain film, and improved resolution of 12 - 25'.

The first systems were all single camera. KH-4 was the first two camera system, using two KH-3 cameras to provide a stereo image. Resolution was only slightly improved(10-25'), but the stereo image gave more useable data. The next improvement was the use of two rather than one recovery vehicle(RV) which allowed two missions from a single launch. This was made possible through the use on strap on rockets on the Thor booster, the so-called Thrust-augmented Thor or Thorad. Which gave greater lift capacity. The KH-4A was a KH-4 with an additional film RV. KH-4A also had a larger payload of film. The KH-4B provided a new generation camera and operating system which allowed lower orbits(down to 80 nm), and greater resolution, generally 6'. In some circumstances, this system provided resolution to 4.5'.

KH-5 was a specialized camera used for the ARGON program, a part of Corona. ARGON was a project to provide broad based mapping for geodetic purposes so that the strategic targets could be pinpointed. ARGON images were 300 miles square, with a resolution of 460'. The first ARGON missions flew independently, but later missions were flown alongside the Corona imaging system. The 12 ARGON missions flew from February 17, 1961 to August 21, 1964, and succeeded in mapping most of the USSR and Eastern block. ARGON launches were identified by an "A" after the Corona launch designator.

The KH-6 system was designed to provide very high resolution photos(2'). The camera was part of a project called LANYARD, another specialized part of Corona. The initial stimulus for this added resolution was suspected ABM sites around Leningrad. The best resolution achieved was 6', the same as the KH-4B, so LANYARD was discontinued after 3 launches in 1963.

Corona used other cameras "piggyback" on the Agena vehicle. ARGON used a secondary mapping camera. KH-3, 4, 4A and 4B used horizon cameras to determine the orientation of the bird, stellar cameras to accurately determine pitch, roll and yaw during operational cycles, and index cameras for small scale photos to help mine the location of the main images

Corona proved to be very successful. The U-2 program mapped 1 million sq. mi. with 24 flights. Corona covered 510 million sq. mi. Corona was important from a technology standpoint. When the project started, no one knew if you could even take photos in space. Corona also provided highly accurate intelligence data for senior US policy makers. The recently released data shows the scope of Corona's success:

Imaged all Soviet medium-range, intermediate-range and ICBM complexes

Imaged each Soviet submarine class from deployment to operational bases

Provided inventories of Soviet bombers and fighters

Revealed the presence of Soviet missiles in Egypt protecting the Suez Canal

Identified Soviet nuclear assistance to the People's Republic of China

Monitored the SALT I treaty

Uncovered the Soviet ABM program and sites (GALOSH, HEN HOUSE, etc.)

Identified Soviet atomic weapon storage installations

Identified People's Republic of China missile launching sites

Determined precise locations of Soviet air defense missile batteries

Observed construction and deployment of the Soviet ocean surface fleet

Identified Soviet command and control installations and networks

Provided mapping for Strategic Air Command targeting and bomber routes

Identified the Plesetsk Missile Test Range, north of Moscow

Since no one knew about Corona until now, no covers were prepared specifically for Corona launches. However, covers were prepared for Discoverer missions and "secret satellites", so covers probably exist for these launches. Horace Westbrooks, in his definitive article on the Discover series notes that Discoverer X "...is the only DISCOVERER for which no philatelic covers are known..." The existence of covers for most of the launches has been verified.

Summary of Corona Missions - Notes to Table

Dates listed in this table reflect those reported by Corona. There are some discrepancies between these dates and those which were reported to national and international authorities, and to which international designations were assigned in order to track objects in space. The US source for such data is the Goddard SFC Satellite Situation Report. These discrepancies also exist with those reported in the philatelic community, which agree entirely with the Goddard report. In many cases, the public, which includes the philatelic community, witnessed these launches, as all launches from Van den Berg are able to be observed due to the proximity of inhabited areas. Discrepancies are noted. It is likely that launches which occurred late in the day were reported the next morning, the date of launch being relatively irrelevant to Corona authorities. The Goddard dates are probably correct. Some Corona numbering is out of sequence.

Covers probably exist for all these launches except 9007(Discoverer X), however all have not been verified. Those not verified are so noted by an asterisk (*) in the mission field. Readers are invited to submit proof of existence, or doubt thereof.

SUMMARY OF CORONA MISSIONS
			Suc-	Rec-
Mission	Date	Satellite	cess	overy	Remarks
9001	590625	KH-1	No	No	Discoverer IV; Agena did not orbit
9002	590813	KH-1	No	No	Discoverer V; Camera failed orbit 1; RV not recovered
9003	590819	KH-1	No	No	Discoverer VI; Camera failed on orbit 2; retrorocket malfunction- RV not recovered
9004	591107	KH-1	No	No	Discoverer VII; Agena filed to orbit
9005	591120	KH-1	No	No	Discover VIII; bad orbit; camera failure; RV not recovered
9006	600204	KH-1	No	No	Discoverer IX; Agena failed to orbit
9007	600219	KH-1	No	No	Discoverer X; Thor failure
9008	600415	KH-1	No	No	Discover XI; camera operated; spin rocket failure; RV not recovered
N/A	600629	N/A	No	No	Discoverer XII; diagnostic flight; Agena failed to orbit
N/A	600810	N/A	Yes	Sea	Discoverer XIII; diagnostic flight; RV recovered
9009	600818	KH-1	Yes	Air	Discoverer XIV; First successful Corona mission
9010	600913	KH-1	No	No	Discoverer XV; camera operated; wrong pitch angle on reentry; no recovery
9011	601026	KH-2	No	No	Discoverer xVI; Agena failed to orbit
9012	601112	KH-2	No	Air	Discoverer XVII; payload malfunction
9013	601207	KH-2	Yes	Air	Discoverer XVIII; first successful KH-2
N/A	601220	N/A	YES	N/A	Discoverer XIX; Radiometric mission
9014A	610217	KH-5	No	No	Discoverer XX; first ARGON flight; orbital programmer failed
N/A	610218	N/A	Yes	N/A	Discoverer XXI; radiometric mission
9015	610330	KH-2	No	No	Discoverer XXII; Agena failed to orbit
9016A	610408	KH-5	No	No	Discoverer XXIII; camera functioned
9018A	610608	KH-5	No	No	Discoverer XXIV; Agena failure; power and guidance failure
9017	610616	KH-2	Yes	Sea	Discoverer XXV;
9019	610707	KH-2	Partial	Air	Discoverer XXVI; camera failed on Rev 22
9020A	610721	KH-5	No	No	Discoverer XXVII; No orbit; Thor malfunction
9021	610803	KH-2	No	No	Discoverer XXVIII; No orbit, agena guidance failure
9022	610830	KH-3	Yes	Air	Discoverer XXIX; first KH-3
9023	610912	KH-2	Yes	Air	Discoverer XXX
9024	610917		No	No	Discoverer XXXI; power failure
9025	611013	KH-3	Yes	Air	Discoverer XXXII
9026	611023	KH-2	No	No	Discoverer XXXIII; Agena failed to orbit
9027	611105	KH-3	No	No	Discoverer XXXIV
9028	611115	KH-3	Yes	Air	Discoverer XXXV
9029	611212		Yes	Sea	Discoverer XXXVI
9030	620113	KH-3	No	No	Discoverer XXXVII; Agena failed to orbit. Covers canceled 1/15/62 for late Saturday launch.
9031	620227	KH-4	Yes	Air	Discoverer XXXVIII; first KH-4
9032	620418		Yes	Air	Reported 4/17/62(cover date)
9033	620428		No	No	Parachute failed to eject
9034A	620515	KH-5	Yes	Air
9035	620530	KH-4	Yes	Air	Reported 5/29/62(cover date)
9036	620602	KH-4	No	No	Torn parachute Reported 6/1/62(cover date)
9037	620622	KH-4	Yes	Air
9038*	620628	KH-4	Yes	Air	Reported 6/27/62(cover date)
9039	620721	KH-4	Yes	Air	Reported 7/20/62(cover date)
9040	620728	KH-4	Yes	Air	Reported 7/27/97
9041	620802	KH-4	Yes	Air	Reported 8/1/62(cover date)
9044*	620829	KH-4	Yes	Air
9042A	620901	KH-5	Yes	Air
9043	620917	KH-4	Yes	Air
9045	620929	KH-4	Yes	Air
9046A	621009	KH-5	Yes	Air
N/A	621026			N/A	Non-photoreconnaissence engineering Flight
9047	621105	KH-4	Yes	Air
9048	621124	KH-4	Yes	Air
9049	621204	KH-4	Yes	Air
9050	621214	KH-4	Yes	Air
9051	630108	KH-4	Yes	Air	Reported 1/7/63(cover date)
9052	630228	KH-4	No	No	Separation failure
8001	630318	KH-6	No	No	First KH-6; Failed to orbit, Agena guidance failure; LANYARD mission
9053	630401	KH-4	Yes	Air
9055A	630426	KH-5	No	No	Failed to orbit, altitude sensor problem
8002	630518	KH-6	No	No	Orbited; Agena failed in flight
9054	630613	KH-4	Yes	Air	Reported 6/12/63(cover date)
9056	630626	KH-4	Yes	Air
9057	630718	KH-4	Yes	Air
8003	630731	KH-6	Partial	Air	Camera failed after 32 hours Reported 7/30/63(cover date)
1001	630824	KH-4A	Partial	Yes	First KH-4A flight; 2 RVs, RV 2 lost
9058A	630829	KH-5	Yes	Air
1002	630923	KH-4A	Partial	Yes	RV-1 recovered; RV-2 lost
9059A	631029	KH-5	Yes	Air
9060	631109	KH-4	No	No	Booster unstable; no orbit
9061	631127	KH-4	No	No	Agena failed; recovery prevented
9062	631221	KH-4	Yes	Air	Last KH-4
1004	640215	KH-4A	Yes	Air
1003*	640324	KH-4A	No	No	Failed to orbit; agena power failure
1005	640427	KH-4A	No	No	No photos; agena failed:RV impacted in Venezuela
1006	640604	KH-4A	Yes	Air
9053A	640613	KH-5	Yes	Air
1007	640619	KH-4A	Yes	Air
1008	640710	KH-4A	Yes	Air
1009	640805	KH-4A	Yes	Air
9054A	640821	KH-5	Yes	Air
1010	640914	KH-4A	Yes	Air
1011	641005	KH-4A	Partial	Yes	No RV-2 recovery
1012	641017	KH-4A	yes	Air	RV-2 recovery in sea due to bad weather
1013	641102	KH-4A	Partial	Air	Both cameras failed on orbit 52
1014	641118	KH-4A	Yes	Air
1015	641219	KH-4A	Yes	Air
1016	650115	KH-4A	Yes	Air
1017	650225	KH-4A	Yes	Air
1018	650325	KH-4A	Yes	Air
1019	650429	KH-4A	Partial	Yes	No RV-1 recovery
1021	650518	KH-4A	Yes	Air
1020	650609	KH-4A	Yes	Yes	Sea recovery on RV-2
1022	650719	KH-4A	Yes	Air
1023	650817	KH-4A	Partial	Air	Forward camera failed
N/A	650902	KH-4A	No		Destroyed on launch by range safety
1024	650922	KH-4A	Yes	Air
1025	651005	KH-4A	Yes	Air
1026	651028	KH-4A	Yes	Air
1027	651209	KH-4A	Yes	Air	Malfunction: control gas loss
1028	651224	KH-4A	Yes	Air
1029	660202	KH-4A	Yes	Air
1030	660309	KH-4A	Yes	Air
1031	660407	KH-4A	Yes	Air
1032	660503	KH-4A	No	No	Agena failed to separate from booster
1033	660524	KH-4A	Yes	Air	Reported 5/23/66(cover date)
1034	660621	KH-4A	Yes	Air
1035	660809	KH-4A	Yes	Air
1036	660920	KH-4A	Yes	Air
1037	661108	KH-4A	Yes	Air
1038	670114	KH-4A	Yes	Air
1039	670222	KH-4A	Yes	Air
1040	670330	KH-4A	Yes	Air
1041	670509	KH-4A	Yes	Air
1042	670616	KH-4A	Yes	Air
1043	670807	KH-4A	Yes	Air
1101	670915	KH-4B	Yes	Air	First KH-4B mission
1044	671102	KH-4A	Yes	Air
1102	671209	KH-4A	Yes	Air
1045	680102	KH-4A	Yes	Air
1046	680314	KH-4A	Yes	Air
1103	680501	KH-4B	Yes	Air
1047	680620	KH-4A	Yes	Air
1104	680807	KH-4B	Yes	Air
1048	680918	KH-4A	Partial	Air	Forward camera failed
1105	681103	KH-4B	Yes	Air
1049	681212	KH-4A	Yes	Air	Degraded film
1106	690205	KH-4B	Partial	Air	Aft camera failed
1050	690319	KH-4A	Partial	Air	Terminated early, agena failure
1051	690502	KH-4A	Yes	Air	Degraded film Reported 5/1/69(cover date)
1107	690724	KH-4B	Partial	Yes	Foreword camera failed; RV-1 recovered in sea; Reported 7/23/69
1052	690922	KH-4A	Yes	Air	Last KH-4A mission
1108	691204	KH-4B	Yes	Air
1109	703004	KH-4B	Yes	Air
1110	700520	KH-4B	Yes	Air
1111	700723	KH-4B	Yes	Air
1112	701118	KH-4B	Yes	Air
1113	710217	KH-4B	No	No	Thor booster failure
1114	710324	KH-4B	Yes	Air
1115	710910	KH-4B	Yes	Air
1116	720419	KH-4B	Yes	Air
1117	720525	KH-4B	Yes	Air	Final Corona mission; final photos returned 5/31/72