Discoverer 17

Summary

Discoverer 17
KH-2 CORONA.jpg
Mission typeOptical reconnaissance
OperatorUS Air Force / NRO
Harvard designation1960 Omicron 1
COSPAR ID1960-015A
SATCAT no.00061Edit this on Wikidata
Mission duration2 days
Spacecraft properties
Spacecraft typeCorona KH-2
BusAgena-B
ManufacturerLockheed
Launch mass1,091 kilograms (2,405 lb)
Start of mission
Launch date12 November 1960, 20:38:00 (1960-11-12UTC20:38Z) GMT
RocketThor DM-21 Agena-B
(Thor 297)
Launch siteVandenberg, LC 75-3-5
End of mission
Decay date29 December 1960 (1960-12-30)
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Perigee altitude190 kilometers (120 mi)
Apogee altitude984 kilometers (611 mi)
Inclination81.8°
Period96.45 minutes
 

Discoverer 17, also known as Corona 9012, was an American optical reconnaissance satellite launched on 12 November 1960 at 20:38:00 GMT. It was the second of ten Corona KH-2 satellites, based on the Agena-B.[1]

Background

Discoverer 17 was the second of the KH-2 Corona spy satellites, which was distinguished from the predecessor KH-1 series in its incorporation of the improved C' camera, which replaced the C model carried on KH-1 missions. The improved camera had variable image motion compensation so that its carrying satellites could be flown in differing orbits. Like the C camera, the C' was manufactured by Fairchild Camera and Instrument under the supervision of Itek,[2]:63–64 a defense contractor that specialized in making cameras for spy satellites.[2]:34

Discoverer 16, the first of the KH-2 series, had failed to reach orbit after its launch on 26 October 1960.[3]

Mission

The launch of Discoverer 17.

The launch of Discoverer 17 occurred at 20:38:00 GMT on 12 November 1960. A Thor DM-21 Agena-B rocket was used, flying from LC 75-3-5 at the Vandenberg Air Force Base.[3] Upon successfully reaching orbit, it was assigned the Harvard designation 1960 Omicron 1. It was the first KH-2 satellite to successfully reach orbit.

Discoverer 17 was operated in a low Earth orbit, with a perigee of 190 kilometres (120 mi), an apogee of 984 kilometres (611 mi), 81.8° of inclination, and a period of 96.45 minutes.[4] The satellite had a mass of 1,091 kilograms (2,405 lb),[5] and was equipped with a panoramic camera with a focal length of 61 centimetres (24 in), which had a maximum resolution of 7.6 metres (25 ft).[6] Images were recorded onto 70-millimeter (2.8 in) film, and returned in a Satellite Recovery Vehicle (SRV). The Satellite Recovery Vehicle used by Discoverer 17 was SRV-507.[5]

Shortly after Discoverer 17 began operations, its SRV separated prematurely. Two days after launch it was deorbited and recovered,[6] however only 52 centimetres (20 in) of film was found to be aboard, and no images were taken.[5][7] Following the separation of the SRV, Discoverer 17 remained in orbit until it decayed on 29 December 1960.[8]

Science Results

In addition to its reconnaissance payload, Discoverer 17 carried a biological research payload, intended to investigate human tissues in space. Since at the time the United States did not publicly acknowledge its reconnaissance satellite programs, this was officially the satellite's primary mission. Unexpectedly high radiation levels during the flight led to the data from this experiment being considered particularly valuable by US Air Force scientists.[5] Nevertheless, "samples of human gamma globulin and rabbit antiserum specific for human gamma globulin showed an increase in reactivity, and samples of synovial and conjunctival cells showed no changes in their cytological characteristics."[9]

References

  1. ^ Krebs, Gunter. "KH-2 Corona". Gunter's Space Page. Retrieved 23 October 2020. CS1 maint: discouraged parameter (link)
  2. ^ a b 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. p. 176. ISBN 1-56098-830-4.
  3. ^ a b McDowell, Jonathan. "Launch Log". Jonathon's Space Report. Retrieved 23 October 2020.
  4. ^ https://nssdc.gsfc.nasa.gov/nmc/spacecraft/displayTrajectory.action?id=1960-015A - 5 September 2019
  5. ^ a b c d Wade, Mark. "KH-2". Encyclopedia Astronautica. Archived from the original on 23 January 2013. Retrieved 26 June 2010. CS1 maint: discouraged parameter (link)
  6. ^ a b "Corona". Mission and Spacecraft Library. NASA. Archived from the original on 3 October 2007. Retrieved 26 June 2010. CS1 maint: discouraged parameter (link)
  7. ^ Pike, John (9 September 2000). "KH-2 Corona". Federation of American Scientists. Retrieved 26 June 2010. CS1 maint: discouraged parameter (link)
  8. ^ McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 26 June 2010. CS1 maint: discouraged parameter (link)
  9. ^ Significant Achievements in Space Bioscience 1958-1964. Washington D.C.: NASA. 1966. p. 70. OCLC 914183237.