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Relay program

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Illustration of a Relay satellite

TheRelay programconsisted of Relay 1 and Relay 2, two early Americansatellitesin ellipticalmedium Earth orbit.[1]Both were primarily experimentalcommunications satellitesfunded byNASAand developed byRCA.[2]As of December 2, 2016, both satellites were still in orbit.[3][4]Relay 1 provided the first American television transmissions across the Pacific Ocean.

Relay 1

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Relay 1 launch: Delta second stage hoisted to mate it with first stage in background
Relay 1 satellite under assembly (1962)

Relay 1was launched atop aDelta Brocket (355/D-15) on December 13, 1962, fromLC-17AatCape Canaveral Air Force Station.[5]Its payload includedradiationexperiments designed to map the Earth'sradiation belts.Apogee was 7500 km; perigee 1300. Thespin-stabilized satellitehad an initial spin rate of 167.3 rpm and an initial spin axis orientation with a declination of -68.3 deg and a right ascension of -56 deg. Its orbital period was 185.09 minutes.[6]Shortly after launch, two basic problems evolved. One was the satellite's response to spurious commands, and the other was the leakage of a high-power regulator. This leakage caused the first two weeks of satellite operation to be useless. After this period, satellite operation returned to normal. The satellite carried one transmitter for tracking and one fortelemetry.The telemetry system wasPCMat 1152 bit/s. Each 128 words per telemetry frame (of one second duration) used 113 words for the particle experiment. The leakage problem caused thespacecraftto revert to a low voltage state early in 1965. Sporadic transmission occurred until February 10, 1965, after which no usable scientific data was obtained. Relay 1 was the first satellite to broadcast television from the United States to Japan. The first broadcast during orbit 2677 (1963-11-22, 2027:42-2048 (GMT), or 1:27 pm Dallas time) was to be a prerecorded address from the president of the United States to the Japanese people, but was instead the announcement of theJohn F. Kennedy assassination.On orbit 2678, this satellite carried a broadcast titledRecord, Life of the Late John F. Kennedy,the first television program broadcast simultaneously in the U.S. and Japan.[7]In later orbits,NBCtransmitted coverage of the funeral procession from the White House to the cathedral.[8][9]In the three days following the Kennedy assassination, Relay 1 handled a total of 11 spot broadcasts; eight to Europe and three to Japan. All the useful passes of the satellite were made available to permit immediate coverage of the tragic events.[10]

In August 1964, this satellite was used as the United States-Europe link for the broadcast of the1964 Summer OlympicsfromTokyo,[11]after the signal was relayed to the United States viaSyncom 3.[2]This marked the first time that two satellites were used in tandem for a television broadcast.[10]

COSPARsatellite ID: Relay 1 1962-Beta-Upsilon 1 (62BU1)

Relay 2

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Project Relay ground station

Relay 2was launched atop aDelta Brocket (373/D-23) on January 21, 1964, fromLC-17BatCape Canaveral Air Force Station.[5]Apogee 7600 km; perigee 1870 km. It was physically similar to Relay 1. Design changes in this satellite improved its performance so response to spurious commands was essentially eliminated.

NASA ceased operations with Relay 2 on September 26, 1965, with the repurposing of theMojave Desert Ground Station,the only one in the world equipped to communicate with the satellite, for use with theApplications Technology Satelliteprogram. The final broadcast was of Sen. B. Everett Jordon (D-N.C.) opening the week-long International Exposition of the American Textile Machinery Association in Exposition Hall in Atlantic City.[12]

One of the two onboardtranspondersoperated normally until November 20, 1966. From that time until its failure on January 20, 1967, it required a longer time than normal to come on. The other transponder continued to operate until June 9, 1967, when it too failed to operate normally.

COSPAR satellite ID: Relay 2 1964-003A

See also

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References

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  1. ^"NASA - NSSDCA - Spacecraft - Telemetry Details".nssdc.gsfc.nasa.gov.Retrieved2022-02-17.
  2. ^abMartin, Donald H. (2000).Communications Satellites(fourth ed.). El Segundo, CA: The Aerospace Press. pp. 8–9.ISBN1-884989-09-8.
  3. ^"Relay 2 Space Object".U.S. Space Objects Registry.Archived fromthe originalon 2016-12-03.Retrieved2016-12-02.
  4. ^"Relay 1 Space Object".U.S. Space Objects Registry.Archived fromthe originalon 2016-12-03.Retrieved2016-12-02.
  5. ^ab"Delta-B".Gunter's Space Page.Retrieved2024-04-10.
  6. ^"Final Report on the Relay 1 Program"(PDF).NASA-SP-76.NASA. 1966. p. 63.Retrieved2021-02-07.
  7. ^"Final Report on the Relay 1 Program"(PDF).NASA-SP-76.NASA. 1966. p. 663.Retrieved2021-02-07.(list of actual orbit dates and times)
  8. ^NBC News(1966).There Was a President.New York:Random House.
  9. ^Shepard, Richard F. (November 26, 1963). "TELEVISION POOLS CAMERA COVERAGE".The New York Times.p. 11.
  10. ^ab"Significant Achievements in Space Communications and Navigation, 1958-1964"(PDF).NASA-SP-93.NASA. 1966. pp. 30–32. Archived fromthe original(PDF)on 2010-05-14.Retrieved2021-02-07.
  11. ^NASA SYNCOM 3 GEOSYNCHRONOUS COMMUNICATIONS SATELLITE PROMO FILM 19114z,retrieved2023-04-07
  12. ^"Aeronautics and Astronautics, 1965"(PDF).NASA. pp. 449–450.Retrieved24 April2020.
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