Direct evidence of field strength above the earth’s atmosphere could be obtained byV2 rocket technique, and it is to be hoped that someone will do something about this soon as there must be quite a surplus stock somewhere.
—Extra terrestrial relays: can rocket stations give world-wide radio coverage, by Arthur C. Clarke. Published in Wireless World
n October 4, 1957, only thirty-six people in the United States could call Europe simultaneously, via AT&T’s recently installed transatlantic submarine cable—TAT-1. If the ionosphere was stable that day, about a further one hundred high-frequency radio circuits would have been available.
AT&T laid TAT-1 in 1956. It was a power-hungry coaxial cable, costing $2 million. To provide enough bandwidth (a wide enough range of frequencies) for live television would have needed twenty such cables. It was not until the mid 1970s that live cable TV was theoretically possible. By then satellites already spanned the oceans, though submarine cables made from optical fibers would mount a stiff challenge to satellites in the 1980s. But that, as they say, is another story.
So, in 1957, two or three people per state could have called Europe at the same time; even fewer could have called countries on the Pacific rim; there was no live transoceanic TV; and the information superhighway was an idea beyond even the most exotic pipe dream. Though computers, television, and telephone all existed, the oceans were truly barriers to communication. And the world that contained these familiar-sounding technologies was very different from our own. After October 4, satellites, too, became a reality. Within decades, communications satellites had done much to change the world. Satellite communication is now a multibillion dollar business. Where did the story begin?
Before there were spacecraft, there were science fiction writers. Most imagined that ground controllers would communicate via radio with their spacecraft. Then in 1945 a junior officer in the Royal Air Force spotted the unique advantages for communication of putting a satellite into an orbit where it maintained the same position with respect to its subsatellite
point—geostationary orbit. The satellite would be like a huge microwave tower. Any antenna on Earth within sight of the satellite could beam a signal to it, which the satellite would then amplify before beaming it back to another antenna at a different spot on Earth.
For a satellite to seem to remain stationary, it must meet two conditions: the orbit must take the same time to complete as the Earth takes to rotate once around its axis (be geosynchronous), and the plane of its orbit must coincide with the plane through the equator (zero inclination). If a geosynchronous satellite has an inclination of zero degrees, it is geostationary, and its place in orbit is designated by the longitude of its subsatellite point on the equator. A satellite is travelling at the velocity needed—more or less—to maintain a geosynchronous orbit when it is at an altitude of about 22,300 statute miles. At such an altitude, the satellite is within site of nearly one third of the Earth’s surface, excluding the poles. In 1959, satellites in this type of orbit were referred to as a 24-hour rather than geostationary satellites.
The junior officer in the RAF imagined that this orbiting telecommunications relay station would carry a crew, which, though wrong, was not a strange thought given the future science fiction career of the young man—Arthur C. Clarke. Clarke ran through some calculations, and in July 1945, he sent an article on the subject to the magazine Wireless World.
The editors were reluctant to publish something that seemed to them like science fiction, and they balked at acceptance. By October, they had relented, and the article appeared in print. It talked of field strengths and transmitter power, of solar power, and of how little time the satellite would spend in the shadow of the earth; and it suggested the best positions in orbit to provide a global system.[14] Clarke’s predictions turned out to be prescient.
At the other side of the Atlantic, an electrical engineer at the Bell Telephone Laboratory, John Robinson Pierce, who knew nothing of Clarke’s article, spent his leisure hours writing short science fiction stories and his working hours immersed in the complexities of microwave communication. Later, it was Pierce who was largely responsible for persuading NASA to carry out communication experiments with the passive Echo spacecraft in August 1960. Like the Moon, which reflected military communications between the East coast and Hawaii, Echo, which acted as a huge mirror in the sky, bounced a signal across the U. S. The two-way Moon relay was operational between 1956 and 1962 and was manned when the Moon was in radio sight of both stations, usually for three to eight hours at a time. Often, when ionospheric storms shut down the usual radio channels, the Moon provided the only link to and from Hawaii for several hours at a time. In 1953, Pierce first suggested that if an artificial reflecting surface could be launched, it could bounce radio signals across oceans.[15]
Pierce joined Bell Laboratories after being awarded his doctorate by the California Institute of Technology in 1936. During World War II, he came across publications by an Austrian refugee, Rudi Kompfner, who was working for the British Admiralty. In 1943, Kompfner invented a class of vacuum tube, known as a traveling wave tube (TWT), that was to have an enormous impact on missile guidance and on communication through submarine cables and via satellite. In 1945, Pierce wrote his first paper about the new concept of traveling wave tubes and developed the first practical application of the technology. Kompfner would later say that he had invented the traveling wave tube but that Pierce had discovered it.
Pierce may as well be allowed to define a TWT in his own words, written in 1990 for a Scientific American publication, Signals, the Science of Telecommunication.
The traveling wave tube is a type of vacuum tube that gives high gain over a broad band of frequencies. An electromagnetic signal wave travels along a spring-shaped coil of wire, or helix, while electrons in the high voltage beam travel through the helix at close to the speed of the signal wave. The electrons transfer power to the wave, which grows rapidly in power as it travels down the helix.
Essentially, the vacuum tube allows electrons to flow from cathode to anode with few collisions and permits an energy exchange from the electron beam to a radio wave constrained to travel the length of the tube. Thus the radio wave is amplified. There have been many versions of TWTs since 1945.
Pierce was impressed by what he knew of Kompfner’s work, and after the war he encouraged senior staff at Bell to recruit Kompfner. They were eventually successful, and Kompfner joined the lab in 1951. Pierce and Kompfner worked together cooperatively and productively for many years, and Kompfner was supportive of Pierces interest in satellites. Their work was the starting point for the Bell team that designed a second type of communications satellite, one with an active repeater that would, like the satellites envisaged by Clarke, amplify the signal before radiating it to Earth. This satellite became known as Telstar.
Telstar was not a twenty-four-hour satellite but rather was planned for a medium-altitude orbit, and so could only be seen by two ground stations simultaneously for about twenty minutes. AT&T calculated that about forty 150-pound satellites in random medium-altitude orbits could provide a communications system with Europe. As soon as one satellite disappeared over the horizon, the transmitting and receiving antennas would lock on to the next mutually visible spacecraft. Such a system, said AT&T in the spring of 1961, could provide sixty channels by 1963 from North America to Europe and three thousand by 1980. The system would give ninety-nine percent probability of a satellite being simultaneously within sight of ground stations located in Maine and in Brittany.
In the summer of 1959, while the lab was still working on Echo, Pierce, Kompfner, and their colleagues at Bell were beginning to think that medium-altitude active repeaters rather than passive satellites were the most promising technology for transatlantic communication. For sound technical reasons, it seemed to them that geostationary satellites would not be feasible for many years.
On the West Coast, unbeknownst to Bell, a handful of engineers— Harold Rosen, Donald Williams, Tom Hudspeth and John Mendel— would soon solve, at least on paper, the problems then facing engineers considering a geostationary orbit. When Leroy Tillotson, at Bell, finished a technical paper on the specifications for a medium-altitude satellite in August 1959 and sent it to Pierce, Kompfner, and other senior members of the research department, Rosen and Williams were putting the finishing touches to their proposal for a twenty-four-hour satellite. The lightweight TWT designed by John Mendel, who had learned his trade in John Pierce’s lab, was critical to the proposal. The proposal, in Rosen’s and Williams’s names, was the beginning of a development that led to Syncom, the first geosynchronous satellite, and to Early Bird, the first commercial communications satellite.
In Arthur C. Clarke’s view, Pierce and Rosen are the fathers of communications satellites. During the early 1960s, however, there was little love lost between the two men. Rosen saw Pierce as obstructionist; Pierce thought that Rosen was making wild claims and would say anything to win support for his twenty-four-hour satellite. It is said they almost came to blows on stage during one conference. Yet they had far more in common than either could have imagined. Both were told at different times by their superiors that they could not go ahead with their work. “Cease and desist,” is what Mervin Kelly, head of Bell Telephone Laboratories, told Pierce in 1958. Both had a fine disdain for the Department of Defense’s plans for a twenty-four-hour satellite and for NASA’s specifications for a medium-altitude active repeater called Relay. Both wanted to keep the government out of communications satellites.
Both, too, had been educated at Caltech, which in the 1930s was like an American Gottingen for the physicists and engineers who would become America’s leaders in aerospace. Pierce was a contemporary ofWilliam Pickering and sought his cooperation for the Echo experiments. Rosen was Pickering’s student and says that he was one of the teachers from whom he learned most. Each left Caltech in little doubt of his own intellectual ability.
The players, then, were John Pierce, Harold Rosen, and Donald Williams, with Tom Hudspeth, Rudi Kompfner, and John Mendel in strong supporting roles. Passive, medium-altitude active, and twenty-four – hour active satellites were the engineering concepts they contemplated.
Men and ideas fitted into a larger, more complex tapestry. It was not just that communications satellites were now within the state of the art, but there was also an increasing commercial and military demand for better communications.
TAT-1 remained the only transatlantic cable for telephony until AT&T laid a second link in 1959, bringing the number of simultaneous calls that cable could carry across the Atlantic to seventy-two. Adding these to the number of high-frequency radio circuits available on a good day, as many as four people per state could simultaneously have called Europe on the day of John Kennedy’s inauguration as president in January 1961. It was still not possible to make live transoceanic TV broadcasts. Instead, recordings were flown by jet or fed slowly down cables.
In response to growth in demand, particularly for calls to and from Europe, AT&T planned to lay a third transatlantic cable in 1963, adding a further two hundred telephone circuits. Even this would not be enough to meet predicted growth in demand. But there seemed to be insurmountable engineering obstacles to developing higher-capacity cables, and the radio spectrum was already overcrowded. Worse still, solar minimum would occur between roughly 1962 and 1966. With less solar energy enveloping Earth, the ionosphere could be less active and thus would not reflect certain frequencies. Experts calculated that this would cut by two – thirds the available high-frequency radio channels worldwide.
The Department of Defense, with troops stationed around the world, often in places with which it was difficult to communicate, was deeply concerned.
With such a paucity of communications infrastructure coupled with the commercial and defense advantages of enhancing communications, it is not surprising that the Kennedy administration placed a high priority on the development of communications satellites. Communications satellites (and meteorology satellites) figured in Kennedy’s famous moon speech of May 25, 1961.
And there were strategic advantages for the United States in developing communications satellites. Communications technology looked as though it could serve as a versatile foreign policy tool that could extend American influence throughout the world. John Rubel, deputy director of defense research and engineering (DDR&E) and for a while the acting director, pointed out in a white paper written in April 1961 that countries newly emerged from colonialism were often reliant for communication on their former colonial powers. He cited the cases of Guinea and Nigeria, which had to go through France and England to communicate with one another. It would be of “incalculable value” in the battle for men’s minds, wrote Rubel, for the United States to maintain a lead in communications technology. “Many feel that the United States should support satellite – based telecommunications systems to achieve these aims, even though there were no immediate commercial advantages resulting therefrom.”
The DDR&E held the third highest civilian position at the Pentagon, roughly on a par in some circumstances with the chairman of the Joint Chiefs of Staff. Thus Rubel was in a position of some influence. He had exerted that influence once, at the prompting of NASA administrator T. Keith Glennan, to change an agreement that NASA and the Defense
Department had made in November 1958, confining NASA to work on passive communications. It was an agreement that deeply frustrated NASA’s engineers at the Goddard Space Flight Center. A new agreement, formalized in August 1960, permitted NASA to work on active communications satellites. Both parties observed a tacit understanding that NASA would work only on medium-altitude satellites, while Department of Defense developed twenty-four-hour satellites.
By April 1961, Rubel seems to have been feeling his way through a complex strategy that would also set aside this second agreement and permit NASA to develop Rosen’s twenty-four-hour satellite. This was necessary because the Defense Department’s own plans for a twenty-four-hour satellite, called Advent, were going disastrously wrong, but there would have been too much opposition to simply canceling the satellite and replacing it with Rosen’s. If, however, the agreement between NASA and Defense could be set aside, then NASA could place a contract for the Rosen proposal. The agreement was dropped.
By August 1961, NASA had placed a sole-source contract with the Hughes Aircraft Company for a twenty-four-hour satellite, and the Department of Defense was to make the Advent ground stations available. The idea was that the twenty-four-hour proposal, now called Syncom, would be a cheap interim satellite to meet military needs until Advent could be developed. A year later, Advent was canceled.
The Syncom decision was a sweet triumph for Harold Rosen and Donald Williams. Before placing a contract for Syncom, both NASA and the Defense Department had been dismissive of Rosen’s and Williams’ engineering concepts. The first Syncom satellites were transferred to the military, and in the mid 1960s these provided links to Southeast Asia in support of America’s growing presence in the region. Thirty years have passed, and Harold Rosen is not yet tired of telling people how the Army and Air Force rejected [his ideas] but within a few years had to rely on Syncom.
By funding the development of Syncom, launching Telstar (at AT&T’s expense) and developing Relay, NASA enabled two approaches to a global satellite communications system to be demonstrated. When the International Telecommunication Satellite Organization (Intelsat) was formed in 1964, it was not yet clear whether international communications would be based on twenty-four-hour satellites or constellations of medium-altitude satellites. If one twenty-four-hour satellite operated successfully, however, Intelsat would know that it was well on the way to providing a global system, whereas tens of Telstar (or Relay-like) satellites would have had to be launched to prove that a global communications system of medium-altitude satellites would work. Thus it was sensible to first launch one twenty-four-hour satellite, and the success of three Syncom satellites was encouraging.[16] The successful launch of Early Bird settled the question, and most commercial communications satellites today occupy geostationary orbits (the countries of the former Soviet Union use another orbit, one better suited to communications at high latitudes).[17]
Though the decision to “go geostationary” has been validated since 1965, the merits of the alternative technological approaches were still being debated in the early 1960s. The technical arguments were enmeshed in and obfuscated by a highly charged policy debate about the role of government versus private industry in the development of communications satellites.
The debate began during the closing months of the Eisenhower administration, when T. Keith Glennan announced that NASA would facilitate the development of communications satellites by providing launch opportunities for industry on a “cost reimbursable basis,” which meant that industry would pay for the launch, but not at a true commercial rate. Glennan, like President Eisenhower, believed that private industry should be involved in the development of communications satellites. At the time, the most aggressive private industry in this field was AT&T. By October 1960 it had started Project TSX, which became Project Telstar, and had begun spending millions. Senior NASA staff and the attorney general were leery of AT&T. The company already had a virtual monopoly on voice transmissions. Neither NASA nor the Justice Department wanted to make decisions that would exclude from the new field companies that were not starting from the strong position of an existing monopoly.
When President Kennedy took office and James Webb replaced T. Keith Glennan, the emphasis shifted somewhat to a concern about how much control the government should retain over the development ol communications satellites given their strategic importance. Webb, whom
AT&T viewed as anti-industry, said that he did not want to put AT&T up against the whole Soviet Union.
Engineers at Bell perceived that the debate had become truly heated in February 1961 when Lloyd Berkner, whose proposal of an International Geophysical Year ten years earlier had set so much in motion, said in a speech that communications satellites would be a billion-dollar business in ten to fifteen years. The newspapers picked up the comment. Congress took note, and the Justice Department quoted Berkner in submissions to the Federal Communications Commission and Congress. Berkner’s comments were used to bolster the argument that space communication was too big for one company. Though his prediction was to prove correct, Berkner modified his views shortly after making them known, making the not unfamiliar claim that the media had exaggerated them.
But verbal arabesques could not change the course of the debate. Berkner had tapped into some widespread and deeply felt issues: the previous administration’s concern about extending AT&T’s monopoly; the current administration’s desire to have some control over the development of a technology with strategic implications for the military, for commerce, and as a foreign policy tool; the current administration’s concern that a private company should not represent the United States in negotiations for a global system; and industry’s objection to being excluded by monopoly power from a potentially lucrative new market.
By February 1962, the Kennedy administration had sent a communications satellite bill to Congress. The bill set up a private company called Comsat under strict governmental control. Half the stock was offered to the general public and half to the common carriers. The Federal Communications Commission was responsible for distributing stock fairly between the common carriers, including AT&T. Key members of Congress had their own ideas about the bill, but by the end of the summer, the Senate had passed it, 66 to 11, and the House by 354 to 9.
President Kennedy signed the Comsat Act on August 31, 1962. It was the death knell for Telstar, though the concept of medium-altitude satellites had not yet been abandoned. Comsat would be the driving force behind the formation of Intelsat and thus behind the “go geostationary” decision. In the larger world of national and international policy, it was surely the right decision. To the engineers at Bell and to John Pierce, the man who pioneered the idea of commercial communications satellites and developed some of the critical technologies, the Comsat decision was a bitter disappointment.
More than thirty years later, in his home in Palo Alto, John Pierce disposes concisely and precisely of questions about his pioneering days, tugging all the while at a bushy eyebrow. With his sloppy yellow Labrador retriever in attendance, Pierce reminisces politely about Echo and Telstar. Clearly, he has told the story many times, and he says,“I prefer to look forwards rather than back.”
Asked to explain how a klystron works, he grows more animated. He becomes even more interested when writing down the names of mystery and science fiction writers he has not previously come across or talking of the Chinese poetry he translates, the haiku he writes, his admiration for Milton and Blake. Only when I asked him about the Comsat decision did passion flash with the sharpness of a disappointment almost, but not quite, forgotten. Pierce, a loyal son of “Ma Bell,” would not leave Bell Labs, so the Comsat decision that excluded AT&T from international communication via satellites excluded him personally from a field he had pioneered.
As Pierce talks, his movements and speech are like those captured on video in the early 1960s, when he was the executive director of research at the Bell Telephone Laboratories. They are characteristically incisive movements, suggestive of someone who does not suffer fools or pretenders gladly. For a while, he thought that Harold Rosen was a pretender. “I was wrong,” he says. He is less charitable about some of those he encountered at NASA headquarters during the Echo and Telstar days.
Pierce retired from Bell Labs in 1971 at sixty-one, an age when, as he says, he was still young enough to do something else. He joined the faculty of the California Institute of Technology for nine years, then moved briefly to the Jet Propulsion Laboratory as chief technologist. He is now visiting professor of music emeritus at Stanford, where he pursues an interest in the psychophysics of music—the relationship between acoustic stimulus and what we perceive internally. It is an interest he developed at Bell in his postsatellite days.
John Pierce’s interest in science started when he was very young and his mother read to him from “very unsuitable books.” Long before he could read, John could say words like electromotive force, even if he didn’t
quite know what they meant. “She was the mechanical member of our family,” recalled Pierce. She also seems to have had faith in Pierces mechanical ability, because when he and his friend Apollo built a glider, she went up with him, apparently unfazed by the earth flashing by beneath her feet. This, despite knowing that the first glider they had built had fallen apart as it taxied for takeoff. “I was crazy in those days,” says Pierce, “doing things with very little information. I call it gadgeteering.”
Pierce studied at Caltech, and after changing his major a few times, he settled for electrical engineering. He graduated in 1933, looked around at his Depression-era employment prospects, and decided he would be better off staying at Caltech. He gained his master’s in 1934 and his doctorate in 1936. This time the world outside the ivory tower was less hostile to him, and Pierce got a job at Bell Laboratories.
He was told to work on vacuum tubes and left to get on with it, despite knowing next to nothing about the topic. This was typical of Bell Laboratories, where there was a lot of intellectual freedom to pursue research as well as the money to pay for it. Perhaps that accounts for the nobel prizes awarded to physicists at the lab.[18]
By the time World War II broke out, Pierce was expert in the basic theory and design of various classes of vacuum tube. He applied that knowledge during the war and learned a lot about electron optics and broadband amplification. Pierce contributed to the body of work that opened the spectrum above thirty megacycles, which before World War II was almost empty of artificial signals. Developing that technology was essential to the feasibility of communications satellites.
It was while undertaking a mathematical analysis of broadband amplification that Pierce came across Rudi Kompfner’s work on traveling wave tubes. He was impressed. He wrote to Kompfner in 1946, adding his voice personally to that of the management whom he had persuaded to recruit Kompfner.
After working on traveling wave tubes, Pierce and others at Bell Labs turned their attention to MASERs (Microwave Amplification by Stimulated Emission of Radiation). These devices generate or amplify microwaves. When they amplify a weak signal, they add little noise. It was the MASER at the heart of the ground antenna that made it possible to pick up the reflected signal from Echo, which was only a million-million-millionth of the ten kilowatt signal beamed to the satellite for reflection across the country. The MASER improved the antenna’s sensitivity by a factor of one hundred compared with what Pierce had envisaged when he first speculated on the use of an Echo-like satellite for communication. And it was this MASER, protected from extraneous ground noise by a horn-shaped dish, with which Penzias and Wilson detected the cosmic background radiation.
So by 1954, many of the ideas and devices that were crucial for Bell’s satellite communication work existed. And it was about now that Pierce became the first of the pioneers of communications satellites, which came about because he wrote science fiction stories (under the pseudonym J. J. Coupling, a concept familiar to electrical engineers). As a science fiction fan and author, Pierce was asked to give a talk on the subject of his choice to the Princeton, New Jersey, branch of the Institute of Radio Engineers. He must have had an erudite audience, given that RCA and Princeton University were nearby
Over the years, Pierce had given talks about man in space, but he decided that for this audience he wanted a less fanciful subject. He began to wonder what role satellites could play in his own field of communication. At the time, says Pierce, communications satellites were “in the air,” though it was a rarefied air. In 1952 he had written an article about interplanetary communication and had concluded that it was easier to communicate between the moon and Earth than across the United States. Now he did some quick calculations of the power needed for transmission to and from orbiting spacecraft and was surprised to discover that communications satellites were feasible.
Pierce gave the talk, which was to form the basis of his pioneering ideas for communication satellites.
Professor Martin Summerfield told Pierce that he should publish his talk. So, in November 1953, Pierce sent an article to Jet Propulsion, the journal of the American Rocket Society, which published it in April 1954.
The paper proposed three types of communications satellite: a one- hundred-foot sphere that could reflect a signal; a hundred-foot mirror in a twenty-four-hour orbit; and an active repeater in a twenty-four-hour orbit. The latter two, while theoretically stationary with respect to the ground, would actually be affected by solar and lunar gravity and so would need steerable ground antennas and stabilization by remote control.
The first of the three options—a hundred-foot sphere—was to be Pierce’s inspiration for the Echo communication experiments in 1958. In 1954, shortly after Pierce’s article was published, the U. S. Navy began experimenting with the voice transmissions to and from the moon that became the moon relay. But the moon is not an ideal reflective surface; its roughness gives multiple echoes at different wavelengths. A smoothly reflecting artificial satellite would, Pierce knew, provide a much higher – quality passive relay.
In 1954, few believed that satellites would be launched. Undeterred by the common view, Pierce told his audience in Princeton and wrote in his paper that if one found a way to build and launch a satellite, two classes of problem would remain, celestial mechanics and microwave communication. First, they would need to know where their satellite was and would be; then they would need to send and receive radio signals. All the satellite operators had to come to grips with celestial mechanics; some, like Transit, needed a very detailed understanding of the earth’s gravitational field and its impact on an orbit. Pierce’s paper acknowledged the problem but devoted more time to the issues of microwave communication: signal losses on passage from the satellite through the ionosphere and atmosphere to Earth (path losses); the diameter of transmitting and receiving antennas; signal frequency and strength; radio beam width; the method selected for superimposing the signal, such as voice or music, onto the radio carrier wave (modulation); the nature of the polarization of the radio beam; the frequency of the carrier radio wave; sources of noise (that is, other frequency sources that would make the signal difficult to hear); the power of the signal; the signal-to-noise ratio and the sensitivity of the receiver. These were among the topics that five hundred scientists and engineers would later address during the Telstar project.
The science fiction books that Pierce had begun reading as a teenager made spacecraft and radio communication commonplace ideas to him. So the topic of his talk to the Princeton radio engineers is not surprising. But his early love of science fiction also held him back. He had been so used to thinking of spacecraft as romantic fantasies that he did not at the time realize how close they were to realization in his own field of communication. Pierce discussed the idea of communications satellites with people around the lab, but he was concerned about the reliability of vacuum tubes (and who better to know their limitations) in space and the limited abilities of the primitive transistors that then existed. “I was conservative about satellites,” he says.
Nonetheless, Pierce was responsible for persuading NASA to conduct communications experiments with Echo.
The satellite that became Echo was not initially intended to be a communications satellite. It was suggested by William O’Sullivan from the Langley Research Center when James Van Allen’s satellite panel was selecting experiments for the International Geophysical Year. O’Sullivan wanted to launch a giant, aluminized Mylar balloon that could be inflated to a diameter of one hundred feet. With its small mass and large surface area, the balloons would be sensitive to comparatively small changes in force and thus would allow scientists to record how atmospheric density varied with position and solar activity and affected Echo’s orbit. Van Allen’s panel thought the balloon would be a good idea if they had sufficient resources for more than four launches.
In spring of 1958, Pierce and Kompfner read about the balloon and realized that it was exactly what Pierce had imagined would make an ideal passive communications satellite. They packed an ohmmeter and went to Langley to measure the conductivity of the plastic balloon. They decided that it would have a high reflectivity for microwaves. They took some samples of the aluminum-coated mylar back to the lab with them and confirmed its reflectivity. All they needed now was someone to launch the balloon. Unfortunately, the balloon was not one of the high – priority experiments for the IGY. NASA had not yet been formed, and the Department of Defense was already thinking in terms of the elaborate satellite that eventually became Advent and was to go so drastically wrong.
That summer, Pierce and Kompfner went to a meeting on communications satellites at Woods Hole. William Pickering (director of the Jet Propulsion Laboratory) was there and showed himself sympathetic to Pierce’s ideas. Pickering suggested to the meeting that O’Sullivan’s balloon would be ideal for a passive communication experiment. If Bell could find someone to launch the satellite, said Pickering, JPL’s Goldstone ground station would participate in coast-to-coast communication experiments. To
Pierce, it seemed that Pickering’s support was vital to the success of the lab’s subsequent discussions with NASA.
Pierce returned from the meeting to a mixed reception. Mervin Kelly, the president of Bell Telephone Laboratories, asked a mathematician to study Pierce’s proposal. The mathematician’s report was negative. Kelly told Pierce to “cease and desist.” Kompfner thought that their plans could go no further, but Pierce developed a severe case of deafness. He continued to think of Kelly as one of his heroes but concluded that “even great men” can be wrong. In October 1958, he delivered a paper on transoceanic communication via passive satellites to a national symposium on extended-range and space communications.
Later that same month, Pierce served as a consultant to the Advanced Research Projects Agency’s ad hoc twenty-four-hour satellite committee. He listened to what he thought were impractical and inefficient proposals from “these completely uninformed men.” It was clear after this meeting, in which elaborate satellites were discussed, that the Department of Defense was not going to launch the hundred-foot balloon. And shortly afterwards the Defense Department and the newly formed NASA agreed that the Department of Defense would develop active satellites and NASA would develop passive ones.
In the meantime, William Pickering had remained interested in a communication experiment, and NASA had been born. The new agency immediately inherited the Langley Research Center and the Jet Propulsion Laboratory.
In November 1958, T. Keith Glennan, NASA’s administrator; Hugh Dryden, the deputy administrator; and Abe Silverstein, the director of space flight development visited Bell. The purpose of the meeting was to discuss global communications problems. Pierce made a general presentation about communications and satellites, and Kompfner talked about components, data processing, and tracking and guidance philosophy. The NASA contingent was interested, but nothing seems to have come of the discussions.
At the end of December, NASA took over Project Vanguard, thus gaining control of a launch vehicle. By January, the agency was showing an interest in BTL’s ideas. On January 22, NASAJPL, and Bell discussed what they hoped to learn from transmitting a signal between the East and West Coasts. Kompfner wrote to Leonard Jaffe, who headed NASA’s communication satellite work, on February 10, urging him to let Bell know soon whether the project with JPL was to go ahead because of the large amount of work that had to be done. Less than a week later Kompfner warned all technical staff that a considerable amount of work of an unusual nature was coming up. Until now, Pierce had been deeply involved in selling the project to NASA. Now he took a back seat. The day-to-day running of the satellite work was handed over to Bill Jakes, who was responsible to Kompfner. At the end of February, Jakes was immersed in technical discussions with NASA about the MASER and how much bandwidth was needed given the signal and its Doppler shift. Pierce was already toying with the idea of active broadband satellite communication. NASA was by now enthusiastic and was contributing more money to Echos than was Bell. The lab was building the horn antenna for experiments.
On June 10, 1959, there was a large meeting of all those involved with the project. O’Sullivan reported that one full-size balloon, including its inflating mechanism, was already being tested.
The balloon was made of 0.0005-inch-thick Mylar, coated by a 2,000 angstrom layer of aluminum. It weighed 136 pounds and had an optical reflectivity of seventy-five percent for tracking and a radio reflectivity of ninety-eight percent. Being passive, it did not have the complicated electronics needed for active repeaters, but it did carry a radio beacon so that it could be tracked by Minitrack. The sphere was to be inflated in one second by the release of four pounds of water through a plastic nozzle in the sphere. Langley calculated that the vapor pressure would last for seven days, and they were testing six subliming solids in an effort to extend the lifetime. After seven days, they expected a gradual loss of pressure because of micrometeorite impacts. The sphere would get wrinkled, decreasing its usefulness as a reflector for communications. Between November 1959 and July 1960, BTL and JPL practiced bouncing signals to one another first off the moon and then, three times, off TIROS. Their pointing accuracy needed to be good because Echo’s dimensions at an altitude of 1,000 nautical miles would be the equivalent of an object a little over an inch long a mile away, and it would be moving at four and a half miles per second.
The first launch attempt failed because the balloon did not inflate. But the second attempt, on August 12, 1960, was a success. Tracking Echo turned out to be tricky. The original plan was that NASA, at Goddard, would compute the orbital parameters and turn them into tracking instructions for Goldstone and the Bell antenna. A. C. Dickieson, Transit’s project manager, writes in an unpublished manuscript that the tapes as received were late and full of errors. More success, he says, was achieved by taking orbital parameters generated by the Smithsonian Astrophysical Observatory and calculating tracking errors locally Errors in orbital prediction were, however, inevitable in the fall of 1960. Only a few months earlier Bill Guier had predicted Transits position in orbit and realized how much more complicated the earth’s gravitational field was going to be than anyone had thought.
From Bell’s perspective, Echo provided background information for system planning and the design of Earth stations—information that fed into the Telstar project. Echo also demonstrated the effectiveness of the lab’s low-noise receiving equipment as well as the predictability and stability of the transmission path.
Echo was the first satellite that was visible to the naked eye, and T. Keith Glennan had anticipated that it would cause a sensation. It did, bolstered by AT&T’s brilliantly executed publicity campaign. On the night of the launch, the company sponsored a news special on NBC. It was replete with portentous music and massive radio telescopes. Another AT&T-sponsored video opened with ‘America the Beautiful’ and tugged at the patriotic heartstrings. AT&T won the publicity stakes hands down, but alienated NASA. The company’s expropriation of Echo did not win it any friends at the agency. Pierce wonders whether AT&T’s publicity success with Echo influenced NASA’s selection of RCA for the Relay satellite. If it did, it was a minor influence compared with the much larger policy issues that were at stake.
Echo’s success, technically and with the public, encouraged AT&T to go ahead with the development of a medium-altitude satellite as a prototype of a global system of communications satellites. That satellite— Telstar—became every bit as famous as its predecessor.
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