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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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Innovate, Invent, Speculate, Communicate
By: Jessamyn Sarcol
(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 History HIS-story & IT’s-storyHIS-story An Arthur C. Clarke mini-biography from Wikipedia online
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
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.
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 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.
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.
Of course! When it comes to inventions:
The topic of money…
The topic of patents…
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 last view of the ACTS spacecraft before it is rocketed to geosynchronous orbit
Picture from the NASA website