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Project Vanguard

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Vanguard rocket onPad LC-18A

Project Vanguardwas a program managed by theUnited States NavyNaval Research Laboratory(NRL), which intended to launch the firstartificial satelliteintolow Earth orbitusing aVanguard rocket.[1]as thelaunch vehiclefromCape Canaveral Missile Annex,Florida.

In response to the launch ofSputnik 1on 4 October 1957, the U.S. restarted theExplorer program,which had been proposed earlier by theArmy Ballistic Missile Agency(ABMA). Privately, however, theCentral Intelligence Agency(CIA) andPresident Dwight D. Eisenhowerwere aware of progress being made by theSovietson Sputnik from secret spy plane imagery.[2]Together with theJet Propulsion Laboratory(JPL), ABMA builtExplorer 1and launched it on 1 February 1958 (UTC). Before work was completed, however, theSoviet Unionlaunched a second satellite,Sputnik 2,on 3 November 1957. Meanwhile, the spectacular failure ofVanguard TV3on 6 December 1957, deepened American dismay over the country's position in theSpace Race.

On 17 March 1958,Vanguard 1became the second artificial satellite successfully placed in a low Earth orbit by the United States. It was the firstsolar-poweredsatellite. Just 15.2 cm (6.0 in) in diameter and weighing 1.4 kg (3.1 lb), Vanguard 1 was described by then-Soviet PremierNikita Khrushchevas, "The grapefruit satellite".[3]Vanguard 1, and the upper stage of its launch vehicle, are the oldest artificial satellites still in space, as Vanguard's predecessors, Sputnik 1, Sputnik 2, and Explorer 1, have decayed from orbit.

Project history[edit]

In the early 1950s, theAmerican Rocket Societyset up an ad hoc Committee on Space Flight, of whichMilton W. Rosen,NRL project manager for theViking rocket,became chair. Encouraged by conversations between Richard W. Porter ofGeneral ElectricandAlan T. Waterman,Director of theNational Science Foundation(NSF), Rosen on 27 November 1954, completed a report describing the potential value of launching an Earth satellite. The report was submitted to the NSF early in 1955.[4]As part of planning for theInternational Geophysical Year(1957–1958), the U.S. publicly undertook to place an artificial satellite with a scientific experiment into orbit around the Earth.

The three services' proposals[edit]

Proposals to do this were presented by theUnited States Air Force(USAF), theUnited States Army(USA), and theUnited States Navy(USN). The Army Ballistic Missile Agency (ABMA) under Dr.Wernher von Braunhad suggested using a modifiedRedstone rocket(see:Juno I) while the Air Force had proposed using theAtlas launch vehicle,which did not yet exist. The Navy proposed designing arocketsystem based on theVikingandAerobee rocketsystems.

The Air Force proposal was not seriously considered, as Atlas development was years behind the other vehicles. Among other limitations, the Army submission focused on the launch vehicle, while a payload was assumed to become available from theJet Propulsion Laboratory(JPL), and the network of ground tracking stations was assumed to be a Navy project. The Navy proposal detailed all three aspects of the mission.[5]

The Navy's project[edit]

In August 1955, theUS DODCommittee on Special Capabilitieschose the Navy's proposal as it appeared most likely, by spring 1958, to fulfill the following:[6]

  1. Place a satellite in orbit during theInternational Geophysical Year.
  2. Accomplish ascientificexperimentin orbit.
  3. Track the satellite and ensure its attainment of orbit.

Another consideration was that the Navy proposal used civiliansounding rocketsrather than military missiles, which were considered inappropriate for peaceful scientific exploration. What went unstated at the time was that the U.S. already had a covert satellite program underway, WS-117, which was developing the ability to launch spy satellites using USAF Thor IRBMs. The US government was concerned that the Soviets would object to military satellites overflying the Soviet Union as they had to various aircraft incursions and the balloons of theGenetrixproject. The idea was that if a clearly "civilian" and "scientific" satellite went up first, the Soviets might not object, and thus the precedent would be established that space wasabove national boundaries.[7]

Designated Project Vanguard, the program was placed under Navy management and DoD monitorship. TheNaval Research Laboratory(NRL) in Washington was given overall responsibility, while initial funding came from theNational Science Foundation.The director wasJohn P. Hagen(1908–1990), an astronomer who in 1958 would become the assistant director of space flight development with the formation ofNASA.[8]After a delay due to the NRL changing the shape of the satellite from a conical shape,[9]the initial 1.4 kg (3.1 lb) spherical Vanguard satellites were built at the NRL, and contained as their payload sevenmercury cell batteriesin ahermetically sealedcontainer, two tracking radio transmitters, a temperature sensitive crystal, and six clusters ofsolar cellson the surface of the sphere. The first satellite was called Vanguard TV3.[10]

NRL was also responsible for developing the Vanguard rocket launch vehicles through a contract to the Martin Company (which had built the Viking rockets), developing and installing the satellite tracking system, and designing, constructing, and testing the satellites. The tracking system was calledMinitrack.The Minitrack stations, designed by NRL but subcontracted to theArmy Corps of Engineers,were 14 stations[11]along a north–south line running along the east coast of North America and the west coast of South America. Minitrack was the forerunner of another NRL-developed system calledNAVSPASUR,which remains operational today under the control of the Air Force and is a major producer of spacecraft tracking data.[6]

Sputnik and Explorer 1[edit]

Vanguard TV3in previous display at the National Air and Space Museum. The antenna rods should extend radially from the body of the satellite, but are bent as a result of damage sustained in the launch failure.
Vanguard rocket explodes seconds after launch at Cape Canaveral (December 6, 1957).

The original schedule called for the TV3 to be launched during the month of September 1957, but because of delays this did not happen.[6]On October 4, 1957, the Vanguard team learned of the launch ofSputnik 1by theUSSRwhile still working on a test vehicle (TV-2) designed to test the first stage of their launcher rocket. While demoralizing to the Vanguard team, Minitrack was successful in tracking Sputnik, a major success for NRL.[12]At 11:44:35 a.m. on December 6, an attempt was made to launch TV-3. TheVanguard rocketrose about 1.2 m (4 ft) into the air when the engine lost thrust, and the rocket immediately sank back down to the launch pad and exploded. The payload nosecone detached and landed free of the exploding rocket, the small satellite's radio beacon still beeping.[13][14]The satellite was too damaged for further use; it now resides in theNational Air and Space Museum.

After the Soviet Union launchedSputnik 2,on November 3, 1957, thenSecretary of DefenseNeil H. McElroydirected theU.S. Armyto use theJuno Iand launch a satellite.[15]On January 31, 1958, the U.S. Army launched theExplorer 1satellite. With the launch of Sputnik 1 and 2 the previous concern, the right of satellite overflight, had become moot: those satellites were launched by an early version of the SovietR-7 rocket,the basis of the USSR's early ICBMs, and definitely military, as well as roughly 40 times larger than the Vanguard launcher.

On March 17, 1958, the program successfully launched the Vanguard satellite TV-4. TV-4 achieved a stable orbit with anapogeeof 3,969 kilometers (2,466 miles) and aperigeeof 650 kilometers (400 miles). It was estimated that it would remain in orbit for at least 240 years, and it was renamed Vanguard I, which in addition to its upper launch stage remains the oldest human-made satellite still in orbit.

In late 1958, with responsibility for Project Vanguard having been transferred toNASA,the nucleus of theGoddard Space Flight Centerwas formed. After four failed launches, the program once again succeeded with SLV-4, renamed Vanguard II.[16]After two more failures, the program ended with the launch of Vanguard III in 1959.

Accomplishments[edit]

Despite being overshadowed bySputnik 1,and having to overcome the widespread humiliation of its unsuccessful early attempts, the Vanguard Project eventually met its scientific objectives, providing a wealth of information on the size and shape of theEarth,density of air,temperature ranges, andmicrometeoriteimpact.[17]The Vanguard 1 radio continued to transmit until 1964, and tracking data obtained with this satellite revealed that Earth is not quite a perfect sphere: it is slightly pear-shaped, elevated at theNorth Poleand flattened at theSouth Pole.It corrected ideas about the atmosphere's density at high altitudes and improved the accuracy of world maps. The Vanguard program was transferred to NASA when that agency was created in mid-1958.

The Vanguard "Satellite Launch Vehicle", a term invented for the operational SLV rockets as opposed to the Test Vehicle TV versions, was a much smaller and lighter launcher than theRedstone-basedJupiter-C/Juno 1rocket which launched theExplorersatellites, or the immenseR-7that theSovietsused to launch the earlySputniks.

The Vanguard 1 program introduced much of the technology that has since been applied in later U.S. satellite programs, from rocket launching to satellite tracking. For example, it validated in flight thatsolar cellscould be used for several years to power radio transmitters. Vanguard's solar cells operated for about seven years, while conventional batteries used to power another on-board transmitter lasted only 20 days.

Although Vanguard's solar-powered "voice" became silent in 1964, it continues to serve the scientific community. Ground-based optical tracking of the now-inert Vanguards continues to provide information about the effects of theSun,Moon,andAtmosphere of Earthon satellite orbits. Vanguard 1 marked its 50th year in space on 17 March 2008.[18]In the years following its launch, the small satellite has made more than 196,990 revolutions of the Earth and traveled 5.7 billion nautical miles (10.6 billion kilometres), the distance from Earth to beyond thedwarf planetPlutoand halfway back. Original estimates had the orbit lasting for 2,000 years, but it was discovered that solar radiation pressure and atmospheric drag during high levels of solar activity produced significant perturbations in theperigeeheight of the satellite, which caused a significant decrease in its expected lifetime to about 240 years.[19]

Launch history[edit]

Test vehicle launches The first Vanguard flight, a successfulsuborbitaltest of theVanguard TV0single-stage vehicle, was launched on 8 December 1956. On 1 May 1957, the two-stage test vehicle TV1 was successfully launched. Vanguard TV2, another successful suborbital test, was launched 23 October 1957.

The Vanguard rocket launched three satellites out of eleven launch attempts:

  1. Vanguard TV3– 6 December 1957 – Failed to orbit 1.36 kg (3.0 lb) satellite – low tank pressure caused engine cutoff T+2 seconds[20]
  2. Vanguard TV3 Backup– 5 February 1958 – Failed to orbit 1.36 kg (3.0 lb) satellite – control failure caused vehicle breakup T+55 seconds[21]
  3. Vanguard 1– 17 March 1958 – Orbited 1.47 kg (3.2 lb) satellite[22]
  4. Vanguard TV5– 28 April 1958 – Failed to orbit 9.98 kg (22.0 lb) satellite – 3rd stage separation failure[23]
  5. Vanguard SLV-1– 27 May 1958 – Failed to orbit 9.98 kg satellite – 2nd stage attitude control failure prevented the 3rd stage from entering the correct angle for orbital insertion[24]
  6. Vanguard SLV 2 – 26 June 1958 – Failed to orbit 9.98 kg satellite – 2nd stage lost thrust after only 8 seconds of burning due to fuel line obstruction[25]
  7. Vanguard SLV 3 – 28 September 1958 – Failed to orbit 9.98 kg satellite – 2nd stage insufficient thrust for orbital insertion due to fuel line obstruction[26]
  8. Vanguard 2– 17 February 1959 – Orbited 10.8 kg (24 lb) satellite[27]
  9. Vanguard SLV 5 – 13 April 1959 – Failed to orbit 10.3 kg (23 lb) satellite – 2nd stage hydraulics failure led to loss of control[28]
  10. Vanguard SLV 6 – 22 June 1959 – Failed to orbit 10.3 kg satellite – 2nd stage exploded due to stuck helium vent valve[29]
  11. Vanguard 3–18 September 1959 – Orbited 22.7 kg (50 lb) satellite[30]

See also[edit]

References[edit]

  1. ^B. Klawans (April 1960).""The Vanguard Satellite Launching Vehicle — An Engineering Summary""(PDF).Report No 11022, PDF of an optical copy.Glenn L. Martin Company. p. 212.
  2. ^PBS.org - NOVA: Sputnik Declassified
  3. ^"Vanguard 1 - the World's Oldest Satellite Still in Orbit".Spacecraft Engineering Department, U.S. Navy. Archived fromthe originalon 19 September 2008.Public DomainThis article incorporates text from this source, which is in thepublic domain.
  4. ^"Vanguard — A History,Chapter 1. Constance M. Green and Milton Lomask, NASA SP-4202. NASA Historical Reference Collection, NASA History Office, NASA Headquarters, Washington, D.C. and ".Archived fromthe originalon 22 June 2010.Retrieved8 October2009.
  5. ^Green & Lomask, 1970loc cit,Chapter 3
  6. ^abc"Stand By Satellite For Take Off".Popular Mechanics.Hearst Magazines. July 1957. pp. 65–69, 216.
  7. ^McDougall, Walter A., (1985)... the Heavens and the Earth
  8. ^"John P. Hagen".NASA.Archived fromthe originalon 10 January 2006.Retrieved5 December2012.
  9. ^Bille, Matt; Lishok, Erika (2003). "Setting the Record Straight".Proceedings of the 41st AIAA Aerospace Sciences Meeting and Exhibit:5.
  10. ^"Stand By Satellite For Take Off".Popular Mechanics.Hearst Magazines. July 1957. p. 67.
  11. ^Bille, Matt; Lishok, Erika (2003). "Setting the Record Straight".Proceedings of the 41st AIAA Aerospace Sciences Meeting and Exhibit:3.
  12. ^Green, Constance McLaughlin; Lomask, Milton."Vanguard: A History".NASA History.National Aeronautics and Space Administration.Retrieved28 April2015.
  13. ^Stehling, Kurt (1961) Project Vanguard
  14. ^Ley, Willy (October 1968)."The Orbit of Explorer-1".For Your Information.Galaxy Science Fiction.pp. 93–102.
  15. ^"The United States Army | Redstone Arsenal Historical Information".Archived fromthe originalon 3 July 2015.Retrieved14 May2015.
  16. ^Green, Constance McLaughlin; Lomask, Milton."Vanguard: A History".NASA History.National Aeronautics and Space Administration.Retrieved28 April2015.
  17. ^Bille, Matt; Lishok, Erika (2003). "Setting the Record Straight".Proceedings of the 41st AIAA Aerospace Sciences Meeting and Exhibit:10.
  18. ^"Public Affairs Office - U.S. Naval Research Laboratory".Archived fromthe originalon 27 September 2011.Retrieved7 November2008.Public DomainThis article incorporates text from this source, which is in thepublic domain.
  19. ^"NASA - NSSDCA - Spacecraft - Details".NASA.Public DomainThis article incorporates text from this source, which is in thepublic domain.
  20. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  21. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  22. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  23. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  24. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  25. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  26. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  27. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  28. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  29. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  30. ^"NASA - NSSDCA - Spacecraft - Details".nssdc.gsfc.nasa.gov.Retrieved30 November2023.
  • Vanguard: a History,Constance Green and Milton Lomask, NASA SP-4202, Government Printing Office, Washington D.C., 1970
  • Project Vanguard,Kurt Stehling, Doubleday & Company, Garden City, N.Y., 1961
  • Nova - Sputnik Declassified,Ref:Paul Dickson, Author -Sputnik: The Shock of the Century
  • McDougall, Walter A. (1985).... Walter A.Garden City, New York: Basic Books N.Y. pp. 119–124.
  • Stehling, Kurt R. (1961).Project Vanguard.Boston: Doubleday & Company. pp. 17–25.

External links[edit]

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