Category Something New Under the Sun

We were pioneers, and we knew it.

—Bill Guier

arsons auditorium was crowded. Everyone was eager to hear the news as it was relayed from the Cape. They knew about the delays that had accumulated during the final countdown, heard the announcement to switch off radio frequency generators at the lab. The moments before a launch are always tense. In the final seconds the tension was alleviated, as the voice from the Cape intoned, “twelve, eleven, ten, eight, whoops, seven, six, five, four, three, two, one.” The Thor-Able rocket lifted off, car­rying Transit 1A aloft. They knew that Air Force radars were tracking its ascent; that engineers were calculating position, cross checking their slide – rule calculations and sending course corrections to the launch vehicle as needed. They heard the satellite’s transmitters and knew that everything was going well.

Then the transmitters stopped. For a while, no one knew what was happening. Then came the news that the third stage had failed. In all prob­ability, it and the satellite burned up on reentry into the atmosphere some­where over the North Atlantic, west of Ireland. Lee DuBois, one of the mechanical engineers, looked around the room. He saw the tears of disap­pointment on his colleagues’ faces.

The progress reports that APL sent to ARPA were as emotionless as those that described the shattering of their best satellite the previous month. The launch failure, it seemed, could be ascribed to the retro rock­ets on the second stage. These rockets were supposed to slow the second stage after separation of the third, so that the second stage would not inter­fere with the third as it coasted away prior to firing its own engine. When the retrorockets failed, the second stage bumped into the third stage, dis­rupting the third stage’s ignition sequence.

Transit 1A’s flight had lasted twenty-five minutes. Its electronics had survived the launch. As soon as the nose fairing that protected the satellite on liftoff had peeled away, all four frequencies were transmitted. The lab
immediately started an analysis of the telemetry, which comprised mea­surements of variables such as the satellite’s temperatures and solar cell voltages.

APL also had some Doppler data from the short period before the signal was lost. They were incomplete; Henry Elliott’s record shows that one signal was lost intermittently. For a while, an operator had locked unwittingly onto some other unknown signal. Signals from a TV station in Baltimore interfered with reception a few minutes later, and halfway through the pass, one of the tracking filters lost its lock. Nevertheless, APL learned enough to confirm “at least partially” that the ground stations’ design and operation worked, according to the progress report.

With the data received the computing team also made a rough cor­rection for ionospheric refraction. Then they set themselves a theoretical problem, imagining that the Doppler data from Transit’s brief sojourn in space had, in fact, come from a satellite in orbit. They attempted their least squares fit. Though they clearly could not check the accuracy of their “orbital determination” against prediction of the satellite’s position during its next orbit, they could check their results against the Air Force’s radar data. They found the least squares fit was closer than it had been for the Sputniks and Explorer 1 and were encouraged. Thus, though the failed launch did not yield what they had hoped for and pointed to problems that needed to be addressed, the team did learn some things.

For a definitive analysis of ionospheric corrections and to begin investigating the earth’s gravitational field they needed a successful launch. The next attempt was set for April 13, 1960. By January of that year, Kershner was coordinating preparations for Transit IB’s launch and that ol Transit 2 A. Transit IB would be similar to the lost satellite, but Transit 2A, scheduled for a June launch, would test different aspects of the proposed navigation system.

Details piled on details. All over the United States, presumably in the USSR as well, teams of engineers and scientists were slowly coming to terms with the complexities of space exploration. Memos in English and Russian were written, which, if they were like Kershner’s, covered an array of newly recognized problems that now are familiar to those in the space business: nose fairing insulation, loads on structures, details about an epoxy bond, maximum satellite skin temperature at launch, radio frequency links, concerns about deflection and vibration characteristics of the launch vehi­cle’s second stage, and on and on.

Simultaneously, preparations were going forward for the satellites that would follow IB and 2 A in the Transit experimental series with the physics, the engineering, and computing all being developed in parallel— at a time when computing and space exploration were new.

At the ground stations, repeated preparations were made during the first three months of 1960 to track one of the Advanced Research Project Agency’s Discoverer satellites, which was carrying a Transit oscillator (ToD Soc Transit on Discoverer).Transit on Discoverer was part of a program to develop precision tracking for reconnaissance satellites, and the launch was postponed repeatedly. The postponements complicated preparations for IB, as did expansion of the Transit control center and its communication links to encompass the other agencies that were now interested in the project and its data, including NASA and the Smithsonian Astrophysical Observatory.

During the same period, Kershner lined up the Naval Ordnance Laboratory to do magnetic measurements and experiments. The Transit team was interested in fitting its satellites with magnets to stop them from spinning (de-spin, in the industry’s jargon), control their attitude, and pro­vide stabilization.

By March, B and 2A were in the final stages of fabrication or test­ing. John Hamblen (who was Harry Zinc’s and Henry Elliott’s boss) decided that some discipline was needed. He had found out that flight hardware had been released before necessary electrical and environmental tests had been run. In a casually typed note he asked that in future those fabricating the satellite proceed to incorporate a component only if an engineer had first signed the test data sheet. Verbal assurances about a par­ticular component, he wrote, would not do. Thus, casually, at APL and doubtless in many other labs, was the need for documentation recognized, documentation that now, assert many engineers and managers, has grown out of proportion to its usefulness.

The year advanced to Wednesday, April 13, 1960. That was a long day at APL. The launch was scheduled for 7:02 A. M. Eastern Standard Time. Once again Parson’s auditorium grew crowded. Probably the room looked as it does in photographs of the launch of Transit 4B. The ashtray filled to overflowing on a table crowded with papers. Gibson, Kershner, and Newton formal in dark suits, others in shirt sleeves. Gib­son standing, pipe in hand. Kershner in headphones, or telephone to one ear, hand covering the other. Newton seated, twisted slightly to view over his shoulder the clock held at eight minutes to launch, frowning, as was Kershner.

For Transit IB, the countdown proceeded. The voice over the inter­com from the Cape would have been saying things like, programmer starts … gyros uncaged… electrical umbilical ejects… lift off (at 7:03 A. M.). But it was not yet time for the champagne. The satellite still had to reach orbit, which it did, though barely Instead of the nominal 500 nautical mile circular orbit, IB went into an orbit with a perigee of 373 nautical miles and an apogee of 748 nautical miles. Such a result was very inaccurate by today’s standards, but more precise orbits had to wait until those designing launch vehicles were able to perfect inertial guidance controls.

Transit IB’s orbit was, however, sufficient to allow APL to begin work checking whether two frequencies would be adequate to correct for ionospheric refraction or whether a greater number would significantly improve the correction. The answer was that two seemed to be sufficient, though more remained to be done before this question was finally settled.

The immediate task on the first day was to determine an orbit, then to predict its position for the next twelve hours. Until midafternoon, there were computer problems. Then at 15:30 they determined their first orbit. The curves did not fit well, but they thought that this might be because the satellite was still spinning. Spinning ceased on April 19. On April 20, they determined another orbit from observations of fifteen passes at five locations. Again there was a poor fit. They decided this time that the prob­lem was noise. Like Transit 1A, Transit IB carried four frequencies for the investigation of ionospheric effects. Now they turned their attention to the second frequency pair, and the fit was better.

With the data from the second frequency pair, they determined satel­lite position to within 150 to 200 feet from observations of a single pass over a limited region of the earth. With data for half a day from the differ­ent tracking stations they could, assuming a simplistic model for the gravi­tational field and uniform air drag, determine satellite position to within one nautical mile. The longer the arc, the poorer the accuracy appeared to be. Something seemed wrong. Over and over again they looked for errors in the data and software. They could find none. It was a troubling situa­tion.

Extrapolating from a day’s observations, they then predicted the fol­lowing day’s orbit. This was what it was all about, developing a way of pre­dicting an orbit so that its coordinates could be uploaded to the Transit satellites twice a day, enabling the submarines to fix position with respect to a satellite in a known position.

The Transit team looked for the satellite at the time and location they had predicted.

And then they knew they were in trouble.

There was a discrepancy of two to three miles between prediction and observation. While this much error had been acceptable when they were first establishing Sputnik’s orbit in the fall of 1957, it was unaccept­able as the basis for a navigation system. “The satellite,” recalls Guier,“was all over the sky.” Again, they thought that it was a problem with the pro­gramming. But it wasn’t. What they had suspected but had not fully rec­ognized, and what O’Keefe had repeatedly warned Guier and Weiffen – bach about, now came to dominate the theoretical analysis of satellite motion. Earth’s gravitational field was far more complicated than anyone then knew. O’Keefe, because he knew about the perturbations in the moon’s orbit, was expecting that satellites in near-Earth orbits would show more pronounced perturbations, but even he could not have antici­pated the huge variation and the complexity of the gravitational field that was to emerge.

For the position fixing accuracies they wanted to achieve, their knowledge of the gravitational forces perturbing near-Earth orbits needed to improve considerably.

There were precedents. Others had wrestled with apparently unruly satellites. Not least of these were the men within whose paradigms early satellite geodesists were working—-Johannes Kepler and Isaac Newton. Both had struggled to understand the nature of orbits as, mystics both, they sought glimpses of fundamental truths about the universe. Kepler’s focus was on the sun’s satellite Mars; Newton’s was on the earth’s moon. In his book The Great Mathematicians, Henry Westren Turnbull writes, “The Moon, for instance, that refuses to go round the Earth in an exact ellipse, but has all sorts of fanciful little excursions of her own—the Moon was very trying to Isaac Newton.”

And very trying would be the motion of satellites in near-Earth orbits to the early satellite geodesists who, with the technology to observe satellite motion in greater detail than could Kepler or Newton, noticed a veritable plethora of fanciful excursions. The forces causing these devi­ations from elliptical motion needed to be accounted for so that their effect on satellite motion could be quantified and thus orbital prediction improved. It turned out also that because the irregularities in the gravita­tional field are due to variations in the Earth’s shape and composition, sci­entists reaped an unexpected and abundant scientific harvest from observa­tions of orbits. Satellite geodesy supplied, for example, some of the evidence for the theory of continental drift and thus for theories like plate tectonics.

APL was one of the early groups observing satellite motion. They were impelled by the unlikelihood that other geodesy programs would meet Transit’s needs by the time the system was scheduled to be opera­tional, at the end of 1962.

Like other satellite geodesists around the world, the Transit team wanted to determine the “figure” of the Earth. The Earth’s figure is not the topography that we see; rather it is a surface of equal gravitational potential (a geoid) that coincides with mean sea level as it would be if the sea could stretch under the continents. This geoid looks like a contour map. It has highs and lows that represent how the gravitation potential differs at a particular geographical location from what the potential would be at that point if the earth were a water-covered, radially symmetrical rotating spheroid (an ellipsoid of revolution), not subject to the gravita­tional pulls that cause tides. This hypothetical surface is known as the ref­erence ellipsoid.

It is the differences in gravitational potential between the figure of the Earth and the reference ellipsoid that geodesists study as they seek clues to the earth’s shape and structure. At first, only the deviations in motion caused by large irregularities, such as the pear-shaped Earth, were included in geoid models. Today’s models include the gravitational conse­quences of localized irregularities in shape or density. In the mid 1990s, the most accurate geoid maps available to civilians were of what is termed “degree and order 70.” Generally speaking, the higher a model is in degree and order, the more detailed is its description of gravitational potentials, in much the same way as a finer scaled topographical map gives greater detail about a piece of terrain. A geoid map, however, cannot be understood by analogy to an ordinary map. The gravitational potential at a given location is attributable not only to the local features, but also to the varying lengths of gravitational pull exerted by everything else. And the higher the degree and order of a geoid map, the more geologists can infer about the Earth’s structure. Geodesists aspire in the next century to satellite-based models that will be accurate to degree and order greater than 300, the goal being

to provide data that will help geophysicists to understand the earth’s geo­logical origins and history

The road to such comprehensive understanding of our Earth opened with the launch of Sputnik 1. Prior to the advent of satellites, geoid maps showed modest highs and lows that were a result of local measurements of gravity. The force of gravity exerted on a satellite’s motion, though, includes the sum of all the gravitational anomalies resulting from every irregularity of shape and density in the Earth. Disentangling these effects and relating them back to a specific aspect of the earth’s physical nature is a little like unscrambling an egg. Nevertheless, with extensive computer modeling the job can be done.

APL produced the first American satellite geodesy map in 1960, a crude affair by comparison with those of today. Guier and Newton led this effort and found that as with orbital determination and satellite navigation, they had again provoked hostility. Their early geoid maps showed far greater highs and low than appeared in maps from presatellite days, and traditional geodesists dismissed them as amateurs.

APL continued to produce geoid maps of increasing sophistication, but much of this work was classified. Civilian scientists at places like the Smithsonian Astrophysical Observatory and the Goddard Space Flight Center soon came to dominate the field, though APL’s work filtered dis­creetly and obliquely along some grapevines.

The lab’s first gravitational model contained a value for the Earth’s oblateness that was more accurate than that existing pre satellites as well as a term describing the pear-shaped Earth. Shortly afterwards Robert New­ton at APL and independently the Smithsonian Astrophysical Observatory made the next big discovery, which was that the Earth is not rotationally symmetric about its axis. Just as the northern and southern hemispheres are asymmetrical, so too were the eastern and western hemispheres. A number of scientists, most particularly the Soviets, had suspected that this might be true. Later on, APL optimized their geoid maps for Transit’s orbit; that is, they only unscrambled those aspects of the egg that affected polar orbits at Transit’s altitude.

The principle involved in extracting information about the Earth from satellite data is simple to explain in general terms, but very difficult to apply in practice: observe the satellite, note its departure from elliptical motion—its “fanciful excursions”—and try to find (in the computer model) what aspect of the Earth’s shape and structure, for example a par­

ticular dense structure or a liquid area, would give rise to the gravitational anomalies that would cause the satellite’s observed departure from an ellipse.

More detailed gravitational models and ionospheric corrections enabled the orbital determination group to improve their knowledge of satellite position from between two and three kilometers in 1959 to a little under one hundred meters by the end of 1964. With problems like iono­spheric refraction corrected for, other problems emerged. Would it be nec­essary, they wondered, to correct for refraction in the lower atmosphere? Such refraction was a source of bias in their data that could make the satel­lite appear to be about half a nautical mile away from its actual position. Helen Hopfield, whose dignified presence could reduce unruly Transit meetings to silence, tackled this problem, and APL made corrections for tropospheric refraction.

When the Transit group compensated for motion of the geographic poles from their mean position in the early 1970s, the satellite’s position was known to within twenty-seven feet. Polar motion, caused by preces­sion of the earth’s spin axis due to the earth’s nonuniform shape and struc­ture, changes the position of a ground station by about a hundred feet per year, thus introducing a small error into the orbital determination and prediction. The error was negligible for navigators but important to sur­veyors.

By the time of the first launch, APL had stopped characterizing orbits solely in terms of Kepler’s elements (as had other groups). First, because motion within a single orbit does not exactly obey Kepler’s sec­ond law—there are small deviations, and the elements are actually average values. Second, even these average values change gradually as the orbit shifts in inertial space because of the gravitational consequences of physical irregularities in the Earth. For navigation and geodesy, averages were not good enough. It was necessary to know as exact a position as possible at given times in the orbit.

So satellite position was expressed in terms of Cartesian coordinates centered on the earth’s center of mass, with one axis aligned with the earth’s spin axis and the other two lying in the Earth’s equatorial plane. The orbital prediction was made by finding the acceleration from New­ton’s second law of motion—the famous F = та that is so crucial to sci­ence and engineering, where F is force, m is mass, and a is acceleration. The value of the force acting at different parts of the orbit comes from the model of gravitation; then numerical integration of the components of acceleration, a = F/m, yields position and velocity at any desired instant of time.

If it had not been for the new generation of computers, typified by the IBM 7090, this work would not have been possible. The 7090 was one of the newest and best when it was installed in August 1960. It could per­form 42,000 additions and subtractions per second and 5000 multiplica­tions and divisions per second, and it could store 32,768 words (approxi­mately 0.03 megabytes). The 7090 was almost fully transistorized, unlike the vacuum-tube Univac.

The Univac had been badly stressed by the orbital determination program, taking eight hours for eight hours worth of prediction. The IBM 7090 could do the same job in an hour. To run the early gravitation mod­els on the Univac, which embodied only a few of the terms representing the earth’s gravitational field, Guier would set aside three or four week­ends. Had the Univac, which contained vacuum tubes with a mean time to failure of between 15 and 20 hours, been called upon to run the gravita­tional models that were to appear in the coming few years, it would undoubtedly have broken down. Even the 7090 would soon have to be updated as the gravitational model grew more intricate. Today Cray super­computers run some of the largest models; desktop machines with Pen­tium or 486 chips can run models of degree and order 50.

During 1960, Newton, Guier, Black, Hook, and others prepared for the transition to the 7090. The programs had to be rewritten in an assem­bly language compatible with the 7090’s architecture. The orbital determi­nation program occupied four or five trays of punch cards. Woe betide the person who dropped one. And drop them they did, recalls Black, with a laugh that has an edge even after thirty years.

Black and his colleagues were also learning—painfully—about soft­ware engineering, a nascent, scarcely recognized field. Black’s job was to get the orbital determination program running. He was starting with the physics developed by scientists like Newton and Guier. They generated the equations representing the physical realities, and as they understood more about what was going on they generated more equations. Black learned early to freeze the program design and fold new equations repre­senting the physicists’ deepening understanding of the situation into the orbital determination program in an orderly fashion rather than piece­meal. That, at least, was his aim; but Black’s position between the scientists

and the programmers who wrote and tested the code was at times unenvi­able. He had to force agreement out of the scientists, and he fought Guier (his immediate boss), Newton, and Kershner, telling them, “You ain’t gonna change this damn thing.”

In 1962, Lee Pryor, who retired in 1995 as the last project manager of Transit, arrived at the lab. Pryor had specialized in computing while tak­ing his degree in mathematics at Pennsylvania State University. His first three months at college were spent writing programs in anticipation of the arrival of Penn State’s first computer. Black says that Pryor was a godsend. When he arrived at APL, the lab was putting the finishing touches to the first “operational candidate” of the orbital determination program. “We just needed to get it out the door,” recalls Pryor.

In 1962, much physics and mathematics remained to occupy the Transit scientists, but the computing was moving from their purview to that of the professional programmers like Pryor who were writing code for an operational situation rather than for research. The move was neces­sary because, while the scientists could write programs for their own research needs, their programs, it seems, could be cumbersome and prone to breakdown in operation.

Once work on the gravitational model was well in hand, it became apparent that the effects of air drag and the pressure of radiation from the sun would have to be considered. These were dealt with in the 1970s pri­marily by an elegant piece of engineering invented by Daniel De Bra from Stanford University. The navigation satellites were placed inside a second satellite. The separation between their faces was tiny. Sensors on the Tran­sit satellite detected when the inner satellite moved toward the outer sur­face, and tiny rockets moved the inner satellite to compensate for these forces, before they could offset the Doppler shift. An engineering solution was necessary because the time, size, and place of the forces could not be predicted.

In the mid 1960s, the failure of solar cells threatened the reliability of the operational Transit satellites. Until this problem was solved with input from Robert Fischell, the Transit satellites tended to fail within a year of launch. Once solved, some veteran satellites exceeded twenty years in operation. The Transit team also launched the first satellite with gravity – gradient stabilization, in which an extended boom encourages the satellite to align itself with the earth’s gravitational field. APL’s first—unsuccess­ful—attempt with this technology was on a satellite known as TRAAC,

Doppler shift due to satellite pass.

which also carried instruments to explore and characterize the Van Allen radiation belts. Ironically, the satellite failed because of ionized particles created artificially by a high-altitude nuclear explosion—as did many other satellites.

TRAAC carried a poem engraved on one of the satellite’s instru­ments. It was written by Thomas Bergen, of Yale University and is reprinted at the end of this chapter. Its mixture of hubris and wistfulness captures something of the atmosphere that surrounded the early work on satellites.

In the case of APL, that work led, of course, to the Navy’s Transit Navigation Satellite System. The lab built the experimental series, the pro­totypes, and many of the early operational satellites. For a time, Navy Avionics built some operational satellites, but the job reverted to APL when these proved unreliable. Eventually, RCA won the commercial con­tract for construction. More satellites were ordered than were needed,

because a problem with the solar cells that was reducing their operational life was solved after the contract was placed.

During the 1980s, under Bob Danchik’s tenure as project manager, when GPS was nipping at Transit’s heels, these satellites were finally launched. The last Transit satellite went into orbit in 1988.

Although there was always at least one operational Transit aloft and available for the submarines from 1964 onwards, the system was not declared fully operational until 1968. At that time four satellites provided global coverage. Not the instantaneous, precise three-dimensional position fix offered by the twenty-four-satellite constellation of GPS, but still, for the first time, an all-weather, global navigation system, a system developed initially for the military, but which evolved until ninety percent of its users were civilian.

In ten years, a newly perceived consequence of the Doppler effect in the three-dimensional world grew through all the stages necessary to design and engineer a space-based navigation system. The program began at a time when vacuum technology was giving way to transistors, when programs were written laboriously in assembly language, and when no one knew how to develop large software applications. The conditions in space were unknown. The physics of the newly entered environment had to be analyzed theoretically and understood experimentally. The complex nature of the earth’s gravitational field had to be researched and a provoca­tive new understanding of the geoid developed. Launch vehicles were imprecise in their placement of satellites, if the satellites reached orbit at all. Satellite design was a new field, with stabilization, attitude control, and communication between space and Earth all unknowns.

During the early development of Transit, the launch vehicle changed, the computers changed, and programs had to be rewritten. Ground stations and satellite test facilities were built. Programs and equip­ment had to be developed for the submarines. It is hardly surprising that one or two people say that they ended up in the hospital, nor that the effort is remembered vividly and affectionately. But as Pryor noted shortly before he retired in 1995, it was time for the Transit program to end.

When the Navy switched off the last Transit satellite in early 1997, it ended the longest-running singly-focused space program to date. It sev­ered the last direct link with the opening of the space age, closing the doors on that shed on the plains of Kazakhstan and on the cold morning when Sergei Korolev thanked his exhausted and elated engineers who had launched Sputnik I, which Guier and Weiffenbach would track, providing the basis for Transit, which helped Polaris, America’s riposte against the Soviet threat of nuclear attack, firing the rockets with whose develop­ment Korolev had been so involved, because he believed that rockets were defense and science, which they became, for both sides, as did Tran­sit, which also became important to civilians. Here is one thread in the Cold War.

And one wonders.

What would have happened if McClure, say, or Pickering, Milton Rosen, or von Braun had met Sergei Korolev? If they had been in a room with chalk, blackboard, and a problem? Faintly, one hears the voices, dis­cerns in imagination the energy and the imminent verbal explosions as Korolev’s little finger lifts toward his eyebrow….

William Pickering’s state of mind and actions following Lloyd Berkner’s toast to the Soviets come from my interview with him. He described also the error in calculation they had made and the phone calls that poured into the headquarters of the IGY (pages 30 — 34).

Information about Project Moonwatch comes from my interviews with Roger Harvey, Henry Fliegel, and Florence Hazeltine.

Information on the radio tracking program comes from interviews by Green and Lomask with Daniel Mazur and Joseph Siry in the NASA His­tory Office, as well as from the following papers: John T. Mengel, “Track­ing the Earth Satellite, and Data Transmission by Radio,” Proceedings of the IRE (44), 6,June 1956;John T. Mengel and Paul Hergert, “Tracking Satellites by Radio,” Scientific American (198), 1, January 1958.

Information about the goals of the IGY satellite program and details of the optical and radio tracking systems and the technical and budgetary difficulties faced comes from minutes of the IGY committees, subcom­mittees, panels, and working groups:

Minutes of the first meeting of the Technical Panel on the Earth Satellite program (TPESP), October 20, 1955. At this meeting the panel defined the program’s goals (page 32).

10 November 1955: An ad hoc meeting of the technical panel on Earth satellites (TPESP) convened to discuss the budget for the program, which had to be ready for a presentation to Congress and the Bureau of the Budget (predecessor to the current Office of Management and Budget) by March 1956. Homer Newell said that important things to be budgeted for were radio and optical tracking and scientific instrumentation. The NRL, who were the experts at radio tracking, wanted stations distributed between latitudes of 35 degrees north and south of the equator. The TPESP wanted to add two more tracking stations to extend coverage to 45 degrees. These tracking stations eventually became known as mini­track.

The optical tracking program was discussed in greater detail at the second meeting of the TPESP, on November 21, 1955. Fred Whipple, director of the Smithsonian Astrophysical Observatory, presented a report prepared by himself and Layman Spitzer. The TPESP recommended that up to $50,000 be awarded to the SAO immediately to set up a series of observ­ing stations. At the time, Whipple’s proposal was for twelve observing sta­tions and an administrative and computer analysis center. He also called for collaboration with amateur observers.

During the third meeting of the TPESP, on January 28, 1956, the difficul­ties of tracking began to emerge. A letter from Homer Newell on the problems of visual and photographic tracking of Earth satellites was read. It was not known whether radio tracking would work (see page 36). The expectation at the time was that there was only a fifty percent likelihood of minitrack succeeding; hence the need for optical tracking.

27 June 1957: The twelfth meeting of the USNC pointed out that there were still problems with the tracking system.

At the seventh meeting of the TPESP on September 5, 1956, John Hagan and Fred Whipple respectively updated the panel on radio and optical tracking. By now, Whipple had made contact with amateurs in an attempt to improve the chances of acquiring the satellite optically. The army, for example, had four hundred binocular elbow telescopes that volunteers, like Florence Hazeltine, could use at military bases.

The twelfth meeting of the TPESP, on October 3, 1957, the eve of the launch of Sputnik, opened with a discussion about how to track a Russian satellite. Fred Whipple explained delays in development of the cameras for optical tracking. It was during this meeting that the delays in delivery of the cameras prompted Richard Porter to say, “I have a number of times threatened to go up to Stanford and beat on tables. … Fred [Whipple] has so far frankly discouraged my doing so.”

At the thirteenth meeting of the TPESP, on October 22, 1957, it was reported that delivery of optics from Perkin Elmer had been increased and brought forward.

The fifteenth meeting of the TPESP, on January 7, 1958, demonstrates the poverty of information about the Sputnik s’ orbits. Whipple said, “We’ve not had a scrap of radio information.” Richard Porter, who headed the panel, said, “We may have underestimated again the difficulty of tracking and photography.” Pickering said, “The Soviet thing caught everyone off base” (page 34).

That the Soviets were also conducting the same basic science experiments and were interested in ionospheric refraction, tracking, and propagation effects comes from Selected Translations from Soviet-Bloc International Geo­physical Year Literature. Artificial Earth Satellite Observations (New York, U. S. Joint Publication Research Services, 1959) and Selected Reports Presented by the USSR at the Fifth Meeting of the Special Committee for the International Geophysical Year (New York, U. S. Joint Publication Research Services, 1958).

Details of the optical tracking program can be found in the annual reports of the SAO for 1961 and 1963.

Green and Lomask (Vanguard—A History, NASA History series SP4202) describe John Mengel’s actions when Sputnik was launched (page 35).

Documents drawn on for the launch of Telstar:

Satellite ground tracking station, Andover, Maine, Engineering notes: Tel­star July 9, 10, and 11, 1962. The document gives details of the count­down (page 188), for example, loss of calibration by the ground tracker at 1220 UT, power supply trouble at 2317 in the upper room of the com­munication antenna, etc. … (box 85080302 – AT&T archives).

Memorandum for the Record from John Pierce, Rudy Kompfner, and Chaplin Cutler on Research Toward Satellite Communication, and Research toward Satellite Communication (page 189). Both are dated Jan­uary 6, 1959, and deal with a research program directed in general at acquiring the basic knowledge for satellite communication by any means and specifically at aspects of passive Echo-type satellites. A fuller version of the research memo was written on January 9, 1959 (AT&T archives).

In this chapter references to what NASA officials said or did (pages 191 to 198) comes from documents in the NASA History Office or George Washington University. These were shared with me by David Whalen.

They include:

Memorandum for the Record, October 31, 1960, by Robert G. Nunn, special assistant to the administrator. This summarizes a meeting between NASA officials and James Fisk, president of Bell Telephone laboratories, and George Best, vice president of AT&T The purpose was to discuss Bell’s plans for “Transoceanic Communication via satellite.” It opened with T. Keith Glennan, NASA’s administrator, saying that Bell had not considered the “facts of life” with respect to vehicle availability. The meeting discussed policy issues in some depth, including finance and whether or why public money should be spent on communication satellites.

Memorandum for program directors, February 24, 1961. Subject: Guide­lines for preparation of preliminary Fiscal Year 1963 budget. On the sub­ject of communication satellites, it said to assume no funding of opera­tional systems; adequate provision should be made for back-up vehicles; and no development of passive communication systems.

Minutes of the administrator’s staff meeting: November 30, 1960; Decem­ber 1, 1960; December 8, 1960; January 18, 1961; January 26, 1961; Feb­ruary 2, 1961; March 2, 1961; May 25, 1961; June 1, 1961; June 12, 1961; June 15, 1961;June 22, 1961;June 29, 1961.

Technical details about Telstar and the attitudes and opinions of the Bell engineers were gleaned from the following:

“Project Telstar, Preliminary report Telstar 1 July—September 1962.” (AT&T archives).

Telstar—The Management Story, by A. C. Dickieson (unpublished manu­script, July 1970). Dickieson was the project manager for Telstar (AT&T archives).

Extracts from a manuscript by D. F. Floth. Chapter on Telstar Planning: January-May 1960 (AT&T Archives 84-0902).

Each quotes extensively from memos that the writers had access to.

The discussions of technology in the chapter come from a mixture of sources, including documents in the Hughes Aircraft Company’s archives.

Helpful textbooks include:

Satellite Communication Systems Engineering, by Wilbur L. Pritchard, Henri G. Suyerhoud, and Robert A. Nelson (Prentice Hall, 1993).

The Communication Satellite, by Mark Williamson (Adam Hilger, 1990).

It was pretty tense because we knew that everybody was watching us, not only this country, but really the whole world, because here the Russians were making a big propaganda hit of how they were launching satellites and we were dropping rock­ets in a ball of fire on our launching pad. We did launch success­fully, at the end of January. That was a very interesting period to live through.

—William Pickering from a transcript of an oral history in the archives of

the California Institute ofTechnology.

n the late 1950s, there was no meeting of minds across the ideological divide.

“The country that gets a manned satellite into space first will be the undisputed master of the entire world. At the present time there is no defense against such a weapon. A satellite in a two-hour pole-to-pole orbit will pass over every part of the world every 24 hours [actually every 12 hours], and the launching of a guided missile against our cities would be a simple matter. Who is to control outer space? Russia? Or the United States?”

So wrote the editor of the Phoenix Republic sometime between Presi­dent Eisenhower’s announcement that the United States would launch satellites and Sputnik Vs arrival in orbit. Though more alarmist than many, the editor expressed a not uncommon fear.

Probably that fear was fueled by extracts from Soviet publications that appeared in the American press, such as the following from Soviet Fleet, a naval paper.

“American imperialists and their henchmen dream of using the pos­sibility of creating an artificial satellite… to set up outer world bases from which it would be possible to deliver attacks against countries of the democratic camp, and to hit the selected objectives.”

Amidst such rhetoric as well as the more measured and weighty crit­icisms of the New York Times, Sputnik II was launched on November 3, 1957. It was the second of three blows that year to America’s perception of its technological supremacy. The third, a month after the second Soviet satellite, would be self-inflicted. Sputnik II prompted yet more questions in

Congress, more headlines, more soul-searching editorials. Congressional critics urged Eisenhower to appoint a missile czar and pour money into education. On the Monday after the launch, Senator Lyndon Johnson spent the day closeted at the Pentagon. On Thursday, Eisenhower went on national television, attempting to reassure Americans that the country was secure. He emphasized the strategic importance of the Air Force, telling his audience that the United States Air Force was as effective as missiles.[8]

But the event that presaged America’s entry to the space age came on Friday, November 8, when Neil McElroy, the secretary of defense, directed the Army to prepare for a satellite launch as part of the Interna­tional Geophysical Year. The Vanguard team, however, was to get the first shot.

That shot took place on December 6. The countdown went smoothly; the launch was a disaster, one that was felt all the more keenly because, unlike the Soviet launches, it took place in full view of the world. Before the entire world, the rocket lifted about two feet off the ground and then burst into flames fourteen stories high. The explosion threw the third stage and satellite clear. The satellite landed on the beach. Its bent antenna beeped to a stunned audience.

J. Paul Walsh, the deputy director for the Vanguard project, had relayed the news over the telephone to listeners at the Naval Research Laboratory. His account was succinct: “Zero, fire, first ignition—explo­sion.”

The moment the news reached New York, there was a dash to unload Martin stock and that of other aerospace companies (though Lock­heed gained). At 11:50, the governors of the stock exchange suspended trading. The next day’s headlines in London included the ignominious words Flopnik and Kaputnik. Humor bolstered America, and people ordered Sputnik cocktails: one part vodka, two parts sour grapes.

There were to be worse failures. Astronauts and cosmonauts would die. In such a complex, unknown, and risky undertaking such disaster was (and is) inevitable. But this one had to hurt. The space community gritted its teeth and prepared for another launch. On January 27, 1958, Vanguard came within fourteen seconds of launch. The attempt was aborted. There was a problem with the second stage. Now, though, America had only four days to wait.

Immediately after McElroy’s direction of November 8, General Medaris, who headed the Army Ballistic Missile Agency (ABMA) in Huntsville, Alabama, had called Pickering, Homer Joe Stewart, and others to a meeting with himself and von Braun. The question was how to carve up the work to achieve a launch sometime toward the end of January, 1958.

Medaris assigned responsibility for the first stage of the launch vehi­cle to von Braun. This was the Redstone rocket, a redesigned and more powerful version of the V2. JPL was given responsibility for the satellite, the tracking stations, and the three upper stages, which would be solid – propellant rockets that the lab had developed. The entire launch vehicle was called Jupiter C.

JPL already had the tracking stations and the rockets because of its ongoing work with the Army exploring designs that would allow a missile to reenter the atmosphere without burning up. But they needed a satellite.

Pickering turned to Van Allen. They had previously talked infor­mally about whether Van Allen’s payload could be modified for an Army launch. Independently, Van Allen had talked in 1956 with staff at ABMA about an alternative, should Vanguard not be ready in time for the I GY. Van Allen would have known that delay was a possibility because Van­guard’s technical director, Milton Rosen, had briefed the IGY’s satellite panel about the technical difficulties with the rocket.

Therefore, once McElroy gave the army the go-ahead, Pickering sought permission from the IGY and Van Allen to prepare Van Allen’s payload for an Army launch. The IGY was the easy part. It was more diffi­cult to reach Van Allen, who was on a research vessel in the Antarctic. There Van Allen wrote in his notebook that Sputnik was a “brilliant achievement.’’ His reaction (and Guier’s) was in contrast to Rear Admiral Rawson Bennett’s comment to NBC that Sputnik I was “a hunk of iron that anyone could launch.”

On the deck of his cold, distant ship, Van Allen felt out of touch with the review of the U. S. program that was taking place. He was concerned that his group might miss a launch opportunity.

Van Allen was particularly worried when JPL acquired responsibility for the satellites (which became known as Explorer), fearing that the lab, which he perceived as very aggressive, would try to take over his experi­ment. His consolation was the confidence he had in Bill Pickering.

Pickering, in fact, went to considerable trouble to contact Van Allen, first with messages via the Navy. When that didn’t work, Pickering recalls that someone suggested Western Union. That succeeded. Van Allen cabled his agreement that his payload should be modified for an Army launch. His assistant, George Ludwig, picked up the bits and pieces around the lab­oratory and, in Pickering’s words, hightailed it out to Pasadena and the Jet Propulsion Laboratory.

The launch was scheduled for the end of January. This time, there was no formal prior announcement, though there were plenty of leaks. Journalists were on the alert. Shortly before the launch, Pickering’s staff were telling callers that Pickering was in New York. A wire reporter, keen to be sure that Pickering was where he was said to be and not in Washing­ton D. C. or at Cape Canaveral, turned up at Pickering’s New York hotel. “Just checking,” the reporter told him.

Days later, Pickering was in Washington—at the Pentagon with von Braun, Van Allen, senior Army personnel, and the secretary of the Army. They were waiting for the launch attempt of what would become 1958 alpha /, better known today as Explorer I. High winds had delayed the shot for twenty-four-hours. But on the evening of January 31, it seemed likely that it would go ahead.

Periodically someone would call the Cape to see how the count­down was faring. At T minus 45 minutes, launch controllers halted the countdown because engineers thought there was a fuel leak. After eigh­teen minutes, they decided there had been a spill during fueling and wiped up the mess. The countdown resumed. The servicing structure rolled back, and its lights went out. Now a search light picked out the silver-gray missile as a Klaxon sounded in warning.

At 10:48, Jupiter C lifted off. When the Redstone finished its burn, von Braun said to Pickering, “Well, now it’s your bird.” The bird had apparently been injected safely into orbit. But to be sure, they had to wait. Not before the tracking station in California picked up the satellite’s signal would they be confident that the spacecraft was orbiting. The only other people on the planet who could really know what that wait was like were in Kazakhstan.

Frank Goddard, at the Goddard Space Flight Center, was waiting to hear from California. Pickering kept a phone line open to him. They had predicted when they should hear the satellite. They waited as the minutes ticked past the time when they should have heard its signal. Pickering felt the glares on his back. Eight minutes after their predicted time, California confirmed that the satellite was in orbit, and the satellite completed its first orbit in the early hours of February 1.

Now von Braun, Van Allen, and Pickering were whisked through the rainy streets of Washington to a press conference at the National Academy of Sciences. They walked into a barrage of lights and microphones. “We didn’t know what we were getting into,” Pickering later recalled. “The place was jammed to the rafters. It was very exciting.”

The news was relayed to President Eisenhower in Augusta, Georgia, where he was enjoying a golfing vacation. He said, “How wonderful.”

Within minutes of the news reaching Huntsville, thousands of people took to the streets, honking car horns and carrying placards that read, “Move over Sputnik, our missiles never miss.”

America had entered the space age.

Before Sputnik I, the United States had planned that its first attempt to launch a full-scale satellite would be in the spring of 1958 and that four test vehicles carrying grapefruit-sized test satellites would be launched in the autumn of 1957. There were hopes that one would attain orbit. In the event, Vanguard put its first grapefruit in orbit on March 17, the day that Frank McClure called Guier and Weiffenbach into his office to discuss how their computational and statistical approach to tracking could serve navigation satellites.

By then, the space community was growing more comfortable with the techniques of satellite tracking. Yet during 1957 they had asked them­selves how they would track all the spacecraft if as many as six were to be launched each year. The question arose in 1957 as the satellite advocates tried to persuade their colleagues to endorse a continuing space program beyond 1958. Now, when TRW’s Space Log reports that by the end of 1987 there had been 2,979 known successful satellite launches (not includ­ing those deployed from the shuttles), that concern exemplifies the adage that the past is another country.

To today’s politically minded citizens, however, yesterday has familiar traces of home, namely budget battles, sniping between participants, and press relations.

By the beginning of 1956 the IGY’s total budget for the satellites and tracking was $19,262,000 an amount that approximately equaled its bud­get for everything else. This did not include the cost of developing and building the launch vehicles. Twelve satellites had been proposed by the scientists. The administration had announced ten in July 1955. By mid 1956, the scientists could count on six but, conservatively, were selecting only four for full development within the IGY’s timetable. All this took place within the context of Defense Department’s budget skirmishes and the rising costs of Vanguard.

The satellite panel was warned to keep the reduction confidential lest it damage America’s international prestige. Some clearly thought that this warning should not be heeded, because stories about the reduced pro­gram trickled out to the press, as did Fritz Zwicky’s comments to the American Rocket Society in November 1956 that “all kinds of jealousies, bureaucracies, and buck passing” were hindering the American satellite program. Many newspapers complained that the Navy should not have got the job of launching a satellite, and others reported on delays in placing of contracts for basic components.

Relations with the press were, in general, a contentious issue be­tween the IGY and the Department of Defense. The scientists grew increasingly irritated because, in their opinion, the Defense Department’s publicity machine made the project look like a military exercise. Not a dif­ficult job given that the Naval Research Laboratory was developing the launch vehicle and that some payloads were being prepared by scientists in defense laboratories. Nevertheless, and despite the fact that many of the university-based scientists had professional relationships at some time with the military, the scientists were determined to ensure that results of exper­iments were published in the open literature so that their international sci­entific relationships would not suffer. One can’t help but wonder what Soviet scientists were going through.

Amidst these concerns perhaps the most intriguing is the one that emerges in a flurry of correspondence in early 1957 that docu­ments that the IGY scientists feared that the Department of Defense would cancel the program once one satellite had been launched suc­cessfully

Nevertheless, planning for four satellites continued. And the space advocates succeeded in their campaign to convince their less enthusiastic colleagues to recommend that the satellite program continue after the IGY. As late as the day before the launch of Sputnik, this was not certain. But Sputnik, of course, changed everything for the space program. Like navigation, meteorology benefited.

Individuals interviewed for the navigation section are as follows:

Bob Danchik* (Transit’s penultimate project manager), Bill Guier* (physics), George WeifFenbach* (physics), Lee Pryor* (software develop­ment and Transit’s last project manager), Carl Bostrom* (physics and later the director of APL), Henry Elliott* (antennas), Lee Dubois* (command, control, and tracking), Charles Pollow* (assistant program manager), Lau­rence Rueger* (time and frequency systems), Tom Stansill* (receivers), Russ Bauer* (software), Charles Bitterli* (software), Harold Black* (physics/orbital mechanics), Ben Elder* (memory designer), Eugene Kylie* (receivers), Barry Oakes* (rf systems), Charles Owen* (mechanical design), Henry Riblet* (antenna design on Transit), Ed Westerfield* (receiver design), John O’Keefe (satellite geodesist), Gary Weir (naval his­torian), Commander William Craft (commander and director of seaman­ship at the U. S. Naval Academy, in Annapolis), Brad Parkinson (GPS pro­ject manager), Group Captain David Broughton (director of the Royal Institute of Navigation), and Dave Smith (satellite geodesist, currently at the Goddard Space Flight Center, Greenbelt, Maryland).

An asterisk denotes that an individual was a member of the Transit team.

Some of the above were interviewed in great depth and over many hours, weeks, and in the case of Guier and WeifFenbach, months; a very few spoke to me for as little as half an hour.

What Pat Hyland thought about Syncom’s early development is found in an extensive video interview recorded on December 14, 1989 (page 199-201). Copy available from НАС.

HAC’s early views on the commercial opportunities of space come from Bob Roney (page 201).

Frank Carver’s request that Harold Rosen look for new business ventures (page 201) was remembered by Harold Rosen and Bob Roney in their interviews with me.

The account of Rosen’s actions and discussion with Williams come from my interview with Rosen (page 202).

The account of Roney’s recruitment of Williams comes from my inter­view with Roney (page 202).

The account of Rosen’s efforts to tempt Williams back to Hughes comes from my interview with Rosen (page 202).

The technology in pages 203 and 204 is my distillation of the technical information in a number of memos, proposals, textbooks, and interviews.

Rosen s attraction to Southern Californian beach parties is his own recol­lection in an interview with me (page 204).

Sydney Metzgers comment (page 204) was made during an interview dated December 5, 1985, when he said, “When we (RCA) heard ofSyn – com we could have kicked ourselves for not thinking of a spinner at syn­chronous altitudes since RCA had the very early spinner experience.” Metzger, who worked for RCA, joined Comsat in June 1963 as the man­ager of engineering (НАС archives 1993-50 Box 1).

Comments on the TWT for HAC’s 24-hour satellite made in interviews with Tom Hudspeth, Rosen and Roney (pages 204 — 205).

The date that Leroy Tillotson sent his proposal for a medium-altitude satellite to Bell’s research department (page 205) is given in A. C. Dick – leson’s book (see notes for chapter 18).

Carver’s and Puckett’s immediate views ol Rosen’s proposal were given in Rosen’s interview with me (page 205).

A memo from A. S. Jerrems to F. R. Carver on September 17, 1959, reminds Carver of a meeting planned for September 23 to work up a pre­sentation on communication satellites for Allen Puckett (page 205) (НАС archives).

Rosen and Williams first describe their satellite in “Commercial Commu­nication Satellite,” October 1959, by H. A. Rosen and D. D. Williams (page 205), and in Preliminary design analysis of communication satellite, October 1959. This paper reviews the torque box design that Harold Rosen and Don Williams put forward for a 24-hour satellite in September (From НАС archives).

Sam Lutz examined the Rosen Williams idea. His evaluation appears in a memo from S. G. Lutz to A. V. Haeff, October 1, 1959, Evaluation of H.

A. Rosen’s commercial satellite communication proposal (From Bob Roney) (page 207).

A memo from A. S. Jerrems of October 9, 1959, confirms the establishment of a two-week-long intensive study of the Rosen proposal (page 207).

A memo from S. G. Lutz to A. V. Haeff on October 13, 1959. Subject: Eco­nomic aspects of satellite communication gives Lutz’s opinions (page 207).

Memo from J. H. Striebel to A. V. HaefF of October 22, 1959. Subject: market study for a worldwide communication system for commercial use shows more of the thinking at НАС (page 207).

Lutz’s second evaluation of the Rosen Williams proposal appears in a memo from S. G. Lutz to A. V. HaefF of October 22, 1959 (page 207). Subject: commercial satellite communication project; preliminary report on study task force.

A memo from L. A. Hyland to A. E. HaefF and C. G. Murphy of October 26, 1959. Subject: communication satellite orders an immediate and com­prehensive study should be made of patentable potentialities and NASA’s position should be ascertained (page 207). A number of subsequent memos show that Hyland’s instructions were carried out. Invention dis­closure was November 2, 1959.

A memo from D. D. Williams to D. E Doody on November 23, 1959 described Williams’s talks on November 5 with Homer Stewart, then at NASA, during which Williams emphasized that Hughes wished to main­tain its proprietary and patent rights and the company’s desire that the project should be undertaken as a commercial venture. The two also dis­cussed technical issues (page 208).

An interesting aside given the later legal action over patents between НАС and NASA is found in a memo from David Doody to Noel Hammond say­ing that should a 30-day analysis then being undertaken by the company show the 24-hour satellite to be feasible, Hughes would attempt to win a contract from NASA and would proceed with filing a patent application prior to contracting with NASA. He said further that the company would not yet enter the communication field or approach communication compa­nies with the proposal. He further wrote, “We will take our chances on retaining title to the inventions that have been made to date, but should NASA insist on taking title as a result of supporting the development, the company wifi go along with NASA since it does not intend to use resulting patents primarily for the purpose of enhancing its patent holdings.” This view is at odds with the decades-long battle that Hughes fought with NASA.

In September 1959, a barrage of technical memos begins covering topics such as dynamic aspects of communication project, feasibility investigation

of payload electronics. The technical memos mushroom during the fol­lowing years.

Despite Hyland’s decision not to commit funds to the 24-hour satellite (page 208) Rosen and Williams write “Commercial Communication Satel­lite”, January i960y by H. A. Rosen and D. D. Williams. By now the 24- hour satellite has the familiar cylindrical shape.

A memo from Robert Roney to A. E. Puckett of 27 January 1960. Sub­ject: communication satellite review analysis (From Bob Roney) describes yet another review of the Rosen/Williams idea (page 208).

On March 23, 1960, Williams wrote to Hyland, saying that he was pleased by Hyland’s decision to fund the commercial communication satellite. He wrote, “It is my understanding that the program will ultimately be financed by sources of capital external to the company. As one of the inventors of the system, I would like to invest in it myself if possible. I enclose a cashier’s cheque for $10,000. While I realize that this amount will not go very far, I think it can be multiplied by 100 if the company is willing to permit investment by its employees.” This was after Rosen, Hudspeth, and he decided to find some of their own money for the pro­ject (page 209).

A memo from Allen Puckett to D. E Doody dated March 7, 1960 details the requests by Williams, Rosen, and Hudspeth to be released from their usual patent agreements should Hughes not go ahead with the develop­ment of a communication satellite. Puckett states that their request is rea­sonable (page 210).

Details of Rosen’s attempts to raise money from various sources are from my interviews with Rosen.