Telstar

Source: Wikipedia, the free encyclopedia.

For other uses, see Telstar (disambiguation).
Not to be confused with Telstra.
Telstar
Space Systems/Loral, Airbus Defence and Space
Country of originUnited States
OperatorAT&T, Telesat
ApplicationsCommunications
Specifications
Regime
Geostationary
Production
StatusIn service
Launched21
Universal newsreel about Telstar 1

Telstar is the name of various communications satellites. The first two Telstar satellites were experimental and nearly identical. Telstar 1 launched on top of a Thor-Delta rocket on July 10, 1962. It successfully relayed through space the first television pictures, telephone calls, and telegraph images, and provided the first live transatlantic television feed. Telstar 2 was launched May 7, 1963. Telstar 1 and 2—though no longer functional—still orbit the Earth.[1]

Description

External audio
audio icon Felker Talking Telstar, 1962, Dr. Jean Felker's speech starts at 4:20, WNYC[2]

Belonging to

NASA (USA), GPO (United Kingdom) and the direction générale des Télécommunications (France) to develop experimental satellite communications over the Atlantic Ocean. Bell Labs held a contract with NASA, paying the agency for each launch, independent of success.[citation needed
]

Six ground stations were built to communicate with Telstar, one each in the US, France, the UK, Canada, West Germany and Italy. The American ground station—built by Bell Labs—was

Fucino, near Avezzano, in Abruzzo
.

The satellite was built by a team at Bell Telephone Laboratories that included

Delta rockets. Telstar was spin-stabilized, and its outer surface was covered with solar cells
capable of generating 14 watts of electrical power.

The original Telstar had a single innovative

transponder that could relay data, a single television channel, or multiplexed telephone circuits. Since the spacecraft spun, it required an array of antennas around its "equator" for uninterrupted microwave communication with Earth. An omnidirectional array of small cavity antenna elements around the satellite's "equator" received 6 GHz microwave signals to relay back to ground stations. The transponder converted the frequency to 4 GHz, amplified the signals in a traveling-wave tube, and retransmitted them omnidirectionally via the adjacent array of larger box-shaped cavities. The prominent helical antenna received telecommands
from a ground station.

Launched by

perigee about 952 km (592 mi) from Earth and apogee about 5,933 km (3,687 mi) from Earth[6]: 3-5  This is in contrast to the 1965 Early Bird Intelsat and subsequent satellites that travel in circular geostationary orbits.[6]
: 3-5 

Due to its non-

passed over the Atlantic Ocean. Ground antennas had to track the satellite with a pointing error of less than 0.06 degrees as it moved across the sky at up to 1.5 degrees per second.[citation needed
]

satellite ground station
in Andover, Maine, built to communicate with Telstar

Since the transmitters and receivers on Telstar were not powerful, ground antennas had to be 90 ft (27 m) tall. Bell Laboratory engineers designed a large horizontal conical

sidelobes, and thus made very low receiving system noise temperatures possible. The aperture of the antennas was 3,600 sq ft (330 m2). The antennas were 177 ft (54 m) long and weighed 380 short tons (340,000 kg). Morimi Iwama and Jan Norton of Bell Laboratories were in charge of designing and building the electrical portions of the azimuth-elevation system that steered the antennas. The antennas were housed in radomes the size of a 14-story office building. Two of these antennas were used, one in Andover, Maine, and the other in France at Pleumeur-Bodou. The GPO antenna at Goonhilly Downs
in Great Britain was a conventional 26-meter-diameter paraboloid.

In service

Telstar 1 relayed its first, and non-public, television pictures—a flag outside Andover Earth Station—to Pleumeur-Bodou on July 11, 1962.

American dollar, which was causing concern in Europe. When Kennedy denied that the United States would devalue the dollar it immediately strengthened on world markets; Cronkite later said that "we all glimpsed something of the true power of the instrument we had wrought."[8][11]

That evening, Telstar 1 also relayed the first satellite

Echo 1, had been used to reflect and redirect communications signals two years earlier, in 1960.) In August 1962, Telstar 1 became the first satellite used to synchronize time between two continents, bringing the United Kingdom and the United States to within 1 microsecond of each other (previous efforts were accurate to only 2,000 microseconds).[13]

The Telstar 1 satellite also relayed computer data between two IBM 1401 computers. The test, performed on October 25, 1962, sent a message from a transmitting computer in Endicott, New York, to the earth station in Andover, Maine. The message was relayed to the earth station in France, where it was decoded by a second IBM 1401 in La Gaude, France.[14]

Telstar 1, which had ushered in a new age of the commercial use of technology, became a victim of the military technology of the

Van Allen Belt where Telstar 1 went into orbit. This vast increase in a radiation belt, combined with subsequent high-altitude blasts, including a Soviet test in October, overwhelmed Telstar's fragile transistors.[15][16][17] It went out of service in November 1962, after handling over 400 telephone, telegraph, facsimile, and television transmissions.[9] It was restarted by a workaround in early January 1963.[18] The additional radiation associated with its return to full sunlight[clarification needed
] once again caused a transistor failure, this time irreparably, and Telstar 1 went back out of service on February 21, 1963.

Experiments continued, and by 1964, two Telstars, two

Syncom 3, broadcast pictures from the 1964 Summer Olympics in Tokyo. The first commercial geosynchronous satellite was Intelsat I
("Early Bird") launched in 1965.

Telstar was considered a technical success. According to a US. Information Agency (USIA) poll, Telstar was better known in Great Britain than

Sputnik had been in 1957.[19]

Newer Telstars

Subsequent Telstar satellites were advanced commercial geosynchronous spacecraft that share only their name with Telstar 1 and 2.

The second wave of Telstar satellites launched with Telstar 301 in 1983, followed by Telstar 302 in 1984 (which was renamed Telstar 3C after it was carried into space by Shuttle mission STS-41-D),[20] and by Telstar 303 in 1985.

The next wave, starting with Telstar 401, came in 1993; which was lost in 1997 due to a magnetic storm, and then Telstar 402 was destroyed shortly after launch in 1994.[21] It was replaced in 1995 by Telstar 402R, eventually renamed Telstar 4.

Telstar 10
was launched in China in 1997 by APT Satellite Company, Ltd.

In 2003, Telstars 4–8 and 13—

Space Systems/Loral, and it was finally launched on June 23, 2005, by Sea Launch
.

Telstar 18 was launched in June 2004 by sea launch. The upper stage of the rocket underperformed, but the satellite used its significant stationkeeping fuel margin to achieve its operational geostationary orbit. It has enough on-board fuel remaining to allow it to exceed its specified 13-year design life.

Telstar 12 Vantage in November 2015 on a H2A204 variant of the H-IIA rocket,[22] and it commenced service in December 2015.[23]

Telstar 19V was launched on 22 July 2018.

Telstar 18V was launched on 10 September 2018, on a SpaceX Falcon 9.[24][25]

Satellites

Name Manufacturer Launch date Launch vehicle Launch place Orbital position Bus Mass
Telstar 1
Bell Laboratories
 July 10, 1962 Delta-DM19
LC-17B
 — Telstar Bus 77 kg (170 lb)
Telstar 2
Bell Laboratories
 May 7, 1963 Delta B
LC-17B
 — Telstar Bus 79 kg (174 lb)
Telstar 301 Hughes July 28, 1983 Delta-3920 PAM-D
LC-17A
 76° W HS-376 625 kg (1,378 lb)
Telstar 302 Hughes August 30, 1984 Space Shuttle Discovery Kennedy LC-39A 125° W HS-376 625 kg (1,378 lb)
Telstar 303 Hughes June 17, 1985 Space Shuttle Discovery Kennedy LC-39A 76° W HS-376 630 kg (1,390 lb)
Telstar 401 Lockheed Martin December 16, 1993
Atlas IIAS
AC-108
LC-36B
 97° W AS-7000 3,375 kg (7,441 lb)
Telstar 402 Lockheed Martin September 9, 1994
Ariane 42L
ELA-2
 89° W
planned 		AS-7000 3,485 kg (7,683 lb)
Telstar 4 Lockheed Martin September 24, 1995 Ariane 42L
ELA-2
 89° W AS-7000 3,410 kg (7,520 lb)
Telstar 5
Space Systems/Loral
 May 24, 1997 Proton-K/Block-DM4 Baikonur 81/23 97° W SSL 1300 3,600 kg (7,900 lb)
Telstar 6
Space Systems/Loral
 February 15, 1999 Proton-K/Block-DM3 Baikonur 81/23 93° W SSL 1300 3,763 kg (8,296 lb)
Telstar 7
Space Systems/Loral
 September 25, 1999
Ariane 44LP
ELA-2
 127° W SSL 1300 3,790 kg (8,360 lb)
Telstar 8
Space Systems/Loral
 June 23, 2005 Zenit-3SL Sea Launch 89° W SSL 1300S 5,493 kg (12,110 lb)
Telstar 9
(not launched)
Space Systems/Loral
 — — — — SSL 1300S 5,493 kilograms (12,110 lb)
Telstar 10
Space Systems/Loral
 October 16, 1997 Long March 3B Xichang 3B 76,5° E SSL 1300 3,700 kg (8,200 lb)
Telstar 11 Matra Marconi Space November 29, 1994
Atlas IIA
LC-36A
 37,5° W Eurostar-2000 2,361 kg (5,205 lb)
Telstar 11N
Space Systems/Loral
 February 26, 2009 Zenit-3SLB Baikonur 45/1 37,5° W SSL 1300 4,012 kg (8,845 lb)
Telstar 12
Space Systems/Loral
 October 19, 1999 Ariane 44LP
ELA-2
 15° W SSL 1300 3,814 kg (8,408 lb)
Telstar 12V
EADS Astrium
 November 24, 2015 H-IIA-204 Tanegashima YLP-1 15° W Eurostar-3000 5,000 kg (11,000 lb)
Telstar 13
Space Systems/Loral
 August 8, 2003 Zenit-3SL Sea Launch 121° W SSL 1300 4,737 kg (10,443 lb)
Telstar 14
Space Systems/Loral
 January 11, 2004 Zenit-3SL Sea Launch 63° W SSL 1300 4,694 kg (10,348 lb)
Telstar 14R
Space Systems/Loral
 May 20, 2011
Briz-M
 Baikonur 200/39 63° W SSL 1300 5,000 kg (11,000 lb)
Telstar 18
Space Systems/Loral
 June 29, 2004 Zenit-3SL Sea Launch 138° E SSL 1300 4,640 kg (10,230 lb)
Telstar 18V
Space Systems/Loral
 September 10, 2018 Falcon 9 B5
SLC-40
 138° E SSL 1300 7,060 kg (15,560 lb)
Telstar 19V
Space Systems/Loral
 July 22, 2018 Falcon 9 B5
SLC-40
 63° W SSL 1300 7,076 kg (15,600 lb)

See also

References

  1. ^ "1962-ALPHA EPSILON 1". US Space Objects Registry. June 19, 2013. Archived from the original on October 5, 2013. Retrieved October 2, 2013.
  2. ^ "Felker Talking Telstar". WNYC. Retrieved October 31, 2016.
  3. ^
    ISBN 0-387-94914-3
    .
  4. ISBN 0-412-57950-2
    .
  5. ^ Markoff, John (January 19, 2004). "James Early, engineer, 81; Helped Create A Transistor". Obituaries. The New York Times.
  6. ^
    OL 2277460M. Retrieved 28 November 2023 – via Google Books
    .
  7. IEEE
    History Center. 2002. Retrieved July 23, 2009.
  8. ^
    NPR
    . Retrieved July 23, 2009.
  9. ^ a b c Clary, Gregory (July 13, 2012). "50th anniversary of satellite Telstar celebrated". Light Years (blog). CNN. Retrieved July 15, 2012.
  10. ^ "Philadelphia Phillies vs Chicago Cubs". Box Score. Baseball-Almanac.com. July 23, 1962. Retrieved July 15, 2012.
  11. ^ Telstar, Kennedy, and World Gold & Currency Markets, YouTube
  12. ^ Video: A Day in History. Telstar Brings World Closer, 1962/07/12 (1962). Universal Newsreel. 1962. Retrieved February 20, 2012.
  13. ^ "Significant Achievements in Space Communications and Navigation, 1958–1964" (PDF). NASA-SP-93. NASA. 1966. pp. 30–32. Retrieved October 31, 2009.
  14. ^ "IBM Archives: IBM and Telstar". www.ibm.com. January 23, 2003. Retrieved May 26, 2019.
  15. ^ Glover, Daniel R. (April 12, 2005). "TELSTAR". NASA Experimental Communications Satellites. Archived from the original on September 5, 2007. Retrieved September 1, 2007.
  16. ^ Early, James M. (1990). "Telstar I – Dawn of a New Age". Southwest Museum of Engineering, Communications and Computation. Retrieved July 11, 2012.
  17. doi:10.1002/j.1538-7305.1963.tb04044.x. Archived from the original
    on August 10, 2013. Retrieved May 18, 2016.
  18. ISBN 0-387-21519-0
    .
  19. ^ Glover, Daniel R. "Chapter 6, NASA Experimental Communications Satellites, 1958–1995". NASA. Retrieved October 23, 2011.
  20. ^ "NASA – STS-41D". NASA. Retrieved July 15, 2012.
  21. ^ "Gas leak led to Telstar 402 explosion". Flight Global. February 28, 1995. Retrieved February 7, 2023.
  22. ^ "Telesat orders high throughput satellite to replace Telstar 12 and expand capacity at 15 Degrees west" (Press release). Telesat. November 24, 2015. Retrieved September 4, 2017.
  23. ^ "Telesat's new Telstar 12 VANTAGE satellite now operational three weeks after launch" (PDF) (Press release). Telesat. December 15, 2015. Retrieved September 4, 2017.
  24. ^ Cooper, Ben (August 22, 2018). "Rocket Launch Viewing Guide for Cape Canaveral". Launchphotography.com. Archived from the original on February 9, 2016. Retrieved August 24, 2018.
  25. ^ "Telstar 18 Vantage Mission". September 10, 2018. Retrieved April 20, 2019.

Notes

  1. ^ Pleumeur-Bodou (48°47′10″N 3°31′26″W / 48.78611°N 3.52389°W / 48.78611; -3.52389)

External links

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