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Arthur C. Clarke The Godfather of The Communications Satellite. Innovate, Invent, Speculate, Communicate. By: Jessamyn Sarcol. The Invention. According to the Wikipedia online, COMMUNICATIONS SATELLITE (also known as COMSAT) is defined as “an artificial satellite stationed in

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arthur c clarke the godfather of the communications satellite

Arthur C. Clarke The Godfather ofThe Communications Satellite

Innovate, Invent, Speculate, Communicate

By: Jessamyn Sarcol

the invention
The Invention
  • According to the Wikipedia online, COMMUNICATIONS SATELLITE

(also known as COMSAT) is defined as “an artificial satellite stationed in

space for the purposes of telecommunications using radio at microwave

frequencies. Most communications satellites use geosynchronous orbits or

near-geostationary orbits, although some recent systems use low Earth-orbiting

satellites. Communications satellites provide a technology that is complementary

to that of fiber optic submarine communication cables.

  • The concept of the communications satellite was first proposed by Arthur C. Clarke,
  • based on Herman Potočnik's pseudonymous work from 1929. In 1945 Clarke published an
  • article titled "Extra-terrestrial Relays" in the magazine Wireless World. The article described the fundamentals behind the deployment artificial satellites in geostationary orbits for the purpose of relaying radio signals. Thus Arthur C. Clarke is often quoted as the inventor of the communcations satellite.”
slide3

The History HIS-story & IT’s-storyHIS-story An Arthur C. Clarke mini-biography from Wikipedia online

  • -born in Minehead, Somerset, England.
  • -As a boy, Clarke enjoyed stargazing and enthusiastically read old American science fiction magazines (magazines which made their way to England as ballast in ships). After secondary school, he was unable to afford college and consequently acquired a job in the government as an auditor.
  • -During World War II, he served in the Royal Air Force (RAF) as a radar specialist and was involved in the early warning radar defense system which contributed to the Royal Air Force's success during the Battle of Britain. After the war, he obtained a degree at King's College, London.
  • -His most important contribution may be the conception that geostationary satellites would be ideal telecommunications relays. He proposed this concept in a scientific paper titled "Can Rocket Stations Give Worldwide Radio Coverage?", published in Wireless World in October 1945. The geostationary orbit is now known as the Clarke orbit in his honor.
  • -In the early 1940s, while he was in the RAF, Clarke began selling his science fiction stories to magazines. Clarke worked briefly as Assistant Editor of Science Abstracts before devoting himself to writing full-time from 1951. He has been chairman of the British Interplanetary Society and a member of the Underwater Explorers Club.
  • -He has lived in Colombo, Sri Lanka, since 1956. This inspired the locale for his novel, The Fountains of Paradise, in which he describes a space elevator. This, he figures, will ultimately be his legacy, more so than geostationary satellites, once space elevators make space shuttles obsolete.
  • -His knighthood was first announced in 1998, but then the British tabloidThe Sunday Mirror published serious accusations against him, and the award was delayed pending investigation. By 2000 it was clear that the story had been planted maliciously. Clarke was then awarded the title of Knight Bachelor at a ceremony in Colombo (his health did not allow him to travel to London to receive the honour personally from the Queen).
it s story a selective communications satellite chronology
IT’s-story: A Selective Communications Satellite Chronology
  • 1945 Arthur C. Clarke Article: "Extra-Terrestrial Relays"
  • 1955 John R. Pierce Article: "Orbital Radio Relays"
  • 1956 First Trans-Atlantic Telephone Cable: TAT-1
  • 1957 Sputnik: Russia launches the first earth satellite.
  • 1960 1st Successful DELTA Launch Vehicle
  • 1960 AT&T applies to FCC for experimental satellite communications license
  • 1961 Formal start of TELSTAR, RELAY, and SYNCOM Programs
  • 1962 TELSTAR and RELAY launched
  • 1962 Communications Satellite Act (U.S.)
  • 1963 SYNCOM launched
  • 1964 INTELSAT formed
  • 1965 COMSAT's EARLY BIRD: 1st commercial communications satellite
  • 1969 INTELSAT-III series provides global coverage
  • 1972 ANIK: 1st Domestic Communications Satellite (Canada)
  • 1974 WESTAR: 1st U.S. Domestic Communications Satellite
  • 1975 INTELSAT-IVA: 1st use of dual-polarization
  • 1975 RCA SATCOM: 1st operational body-stabilized comm. satellite
  • 1976 MARISAT: 1st mobile communications satellite
  • 1976 PALAPA: 3rd country (Indonesia) to launch domestic comm. satellite
  • 1979 INMARSAT formed.
  • 1988 TAT-8: 1st Fiber-Optic Trans-Atlantic telephone cable
  • According to the NASA Headquarters website (http://www.hq.nasa.gov/office/pao/History/satcomhistory.html), David J. Whalen reports the chronological list above.

For a more detailed information on the satellites’ chronological development under NASA, refer to this specific link from the NASA homepage -> http://roland.lerc.nasa.gov/~dglover/sat/chrono.html

slide5

The First Stages…

Random Fact:

During a test of the Echo deployment in 1962, which was three years after Shotput's first failed deployment of the Echo satelloon, a structural load problem caused the balloon once again to explode. A camera aboard the launcher captured these images. The earlier Shotput failure would have looked very much the same.

Echo I

  • Please note that the following pictures are from the Aeronautics and Astronautics at the University of Washington website.
the progress
The Progress…

Telstar was the first

active communications satellite.

Belonging to AT&T as part of a a

multi-national agreements betwe

-en AT&T, Bell Telephone Laboratories, NASA, the

British General Post Office, and the French National

PTT (Post Office.) to develop satellite

communication. It was launched by NASA from

Cape Canaveral on July 10, 1962, the first privately

sponsored space launch. Telstar was placed in an

elliptical orbit (completed once every 2 hours and

37 minutes), rotating at a 45 degree angle above

the equator.

the success
The Success…

The first geosynchronous communications satellite was Syncom 2, launched on July 26, 1963. However, Syncom 2 was positioned in an inclined orbit so special tracking equipment was needed to see it. The first

geosynchronous communications satellite

that could be seen from a fixed satellite

antenna (over North America) was Anik 1,

a Canadian satellite launched in 1973

“The Syncom satellites were 71 cm diameter, 39 cm high cylinders. The fully fueled mass of the spacecraft was 68 kg. The nozzle of the solid propellant apogee motor (1000-lb-thrust designed to impart a velocity increase of 1431 meters/sec) extended from the bottom of the cylinder and a co-axial slotted array communications antenna from the top. The radial exterior was covered with 3840 P-on-n silicon solar cells which provided direct power of 29 watts the 99 percent of the time the spacecraft was in sunlight. Nickle-cadmium rechargeable batteries provided power when the spacecraft was in the Earth's shadow. Most of the central interior of the spacecraft consisted of the tanks and combustion chamber for the apogee motor, around this were arranged two hydrogen peroxide and two nitrogen tanks and the electronics. Attitude and velocity control was provided by nitrogen jets to align the spin axis and hydrogen peroxide jets to position the satellite. Syncom employed a redundant, frequency-translation, active repeater communication system designed to handle one two-way telephone or 16 one-way teletype channels. One receiver had a 13 megacycle bandwidth for TV transmission, the other a 5 megacycle bandwidth. The receiving gain was 2 dB through the slotted dipole antenna. Signals were received on two frequencies near 7360 megacycles and retransmitted on 1815 megacycles. The slotted dipole transmitting antenna radiated a pancake-shaped beam 25 degrees wide with its plane perpendicular to the spacecraft spin axis. There were also four whip antennas oriented normal to the spin axis for telemetry and command (http://nssdc.gsfc.nasa.gov).”

3 different Syncoms were launched. Then, it was followed by the Applications Technology Satellite program with six different satellites so far. There was also the Communications Technology Satellite and the last reported satellite on the NASA website is the Advanced Communications Technology Satellite (ACTS) with the Transfer Orbit Stage (TOS) booster, which was launched on September 12, 1993.

the interview with the godfather
The Interview with the “GODFATHER”

Q & A based on the scientific autobiography,“Ascent To Orbit,” of Mr. Clarke

Q: Why do you call yourself the “godfather” of COMSAT?

A: Well, Dr. John Pierce was the first engineer-scientist to publish a detailed technical analysis of communications satellites. Even more important, he was the driving force behind the poineering practical demonstrations with ECHO and TELSTAR. He and Dr. Harold Rosen—who played a similar role with the first geostationary comsats—are the true fathers of satellite communications. The title of Father of COMSATs has sometimes been given to me, but honesty compels me to disclaim it. I am not the father of comsats—merely the Godfather…

Q: Can you please give us a brief introduction on when and how your interest on communications satellite began?

A: The Wireless World paper was written in late June and submitted to the RAF censor on July 7 and its title was changed from “The Future of World Communications” to “Extra-Terrestial Relays.” I did not recall any serous adverse criticisms, but I had learn later that it had a considerable influence in all sorts of places. The U.S. Navy’s interest, I later discovered, was responsible for the first presentation of the concept to the general public.

Sputnik was still almost twelve years ahead. TELSTAR five years after that- and Early Bird, the first commercial geostationary communications satellite, was launched just twenty yeaes after the publication of my paper.

the controversy
The Controversy

Of course! When it comes to inventions:

The topic of money…

The topic of patents…

The controversy…

Q: Why did Mr. Clarke not patent the communication satellite???

A: I have often been asked—usually pityingly--why I made no attempt to patent the communications satellite. Perhaps the most truthful answer is that I never really expected to see it in my lifetime; I also (though in more cynical moments I am sceptical about this) seem to reccall thinking that it was an idea for all humanity, so I should publish to prevent anyone else from taking out a patent. As indeed I did…

I learned from my patent attorney that even if I had tried to patent communications satellites in 1945, the patent would have been rejected because the required technology did not yet exist, and the patent wouldn’t have been worth getting because its life would only have been 17 years. The patent would have expired the year before Early Bird was launched.

Note: The following responses by Mr. Clarke are direct quotes from his scientific autobiography.

the communications satellite msn encarta
The Communications Satellite (MSN Encarta)
  • “Commercial satellites provide a wide range of communications services. Television programs are relayed internationally, giving rise to the phenomenon known as the “global village.” Satellites also relay programs to cable television systems as well as to homes equipped with dish antennas. In addition, very small aperture terminals (VSATs) relay digital data for a multitude of business services. Intelsat satellites now carry over 100,000 telephone circuits, with growing use of digital transmission. Digital source coding methods (see Telecommunications) have resulted in a ten-fold reduction in the transmission rate needed to carry a voice channel, thus enhancing the capacity of existing facilities and reducing the size of ground stations that provide telephone service.
  • The International Mobile Satellite Organization (INMARSAT), founded in 1979 as the International Maritime Satellite Organization, is a mobile telecommunications network, providing digital data links, telephone, and facsimile transmission, or fax, service between ships, offshore facilities, and shore-based stations throughout the world. It is also now extending satellite links for voice and fax transmission to aircraft on international routes.
  • The latest development in satellites is the use of networks of small satellites in low earth orbit (2,000 km (1,200 mi) or less) to provide global telephone communication. The Iridium system uses 66 satellites in low earth orbit, while other groups have or are developing similar systems. Special telephones that communicate with these satellites allow users to access the regular telephone network and place calls from anywhere on the globe.

The last view of the ACTS spacecraft before it is rocketed to geosynchronous orbit

Picture from the NASA website