THE MOONBOUNCE ZEITGEIST
Project Diana and its goal of bouncing radio waves off the moon did not come out of nowhere. Innovations in radio detection methods, especially by the British and largely driven by the exigencies of war, inspired radio scientists and engineers around the world to realize that these new technologies, many involving the use of higher frequencies, potentially put the moon within reach as a communications satellite that might be enlisted in the war effort. W. John Bray, a communications engineer (and later Director of Research) at the British Post Office Research Station, is credited with being the first to make this observation. Jack Hobart Piddington, an Australian physicist and radar scientist, echoed Bray's sentiments: "With the enormous powers available from R.D.F. [radio direction finding; i.e. radar] equipment, the possibility of obtaining echoes from the Moon appears worthy of investigation."
Another radio specialist to recognize this possibility early on was the American Jack DeWitt--a ham radio operator and founder of Nashville, Tennessee's first radio broadcasting station, as well as a skilled astronomer—who wrote in his notebook on May 21, 1940, “It occurred to me that it might be possible to reflect ultrashort waves from the moon. If this could be done it would open up wide possibilities for the study of the upper atmosphere.” But while Bray and Piddington were still pondering the possibility of moonbounce, Dewitt was not merely theorizing; as it happened, the day before he made this notebook entry, he had actually launched a serious though unsuccessful attempt to bounce 2-meter radio waves off the moon. Undaunted, he attributed his failure to lack of receiver sensitivity and remained supremely confident that with additional refinements of his equipment he could succeed. Before he had a chance to try again, however, the US entered World War II, and he joined the Army Signal Corps.
In an odd quirk of history, a few accidental moonbounces were observed in 1943-44 by a group from Telefunken led by Wilhelm Stepp, whose assignment was to develop a system for detecting near-ground targets (ships, vehicles, low-flying aircraft). One of his technicians, Willi Thiel, told him about a strange perturbation he had observed the day before that he could not explain, which gradually subsided after a couple of hours. Stepp was able to repeat the observation: "The fault happened only when the antenna beamed east, disappeared at once after larger changes of the bearing and appeared with a two seconds delay when beaming east again. It seemed we targeted the moon behind the clouds." Soon afterwards the system was turned over to the German military; no further study of the phenomenon was carried out.
Shortly after the War, Stepp returned to graduate school and wrote his dissertation on his theoretical and experimental work in radar--burying in a footnote a single sentence about the unplanned moonbounces. He also mentioned his observations casually at a couple of professional conferences. Some three decades later, in 1974, he published the only report of the finding to appear in the scientific literature, a brief notice in an obscure nautical journal, crediting Thiel with the discovery and providing a few technical details. His modesty was probably at least in part a tacit acknowledgment that he had not recognized the most important aspect of the feat, its communications potential. Still, just enough information about these chance observations surfaced over the years to rescue them from the dustbin of history and to elicit a few snarky remarks about primacy.
It was only with the end of World War II that research specifically intended to prove that the earth's atmosphere could be penetrated, and to investigate the potential of bouncing radio waves off the moon not only for defense purposes but for applications such as communications and radar astronomy, got underway. The field was developing so explosively that groups sprung up more or less simultaneously and independently, without necessarily knowing much about what other such groups were doing.
Project Diana, under the leadership of the same Jack DeWitt who had tried and failed to shoot the moon in 1940, was the first of these purpose-driven efforts to succeed, on January 10, 1946. Interestingly, because the heavy and ungainly Project Diana antenna could not be tilted but only rotated in azimuth, it was subject to the same time limitations as the Telefunken group had noticed: Moonshots could only be attempted twice a day, usually at moonrise but occasionally at moonset, during the 40-minute window that opened when the moon passed through the 15-degrees-wide beam of the antenna pattern.
The pre-eminent radar research group in the United States at the time was in fact not the little Army Signal Corps team in Belmar, New Jersey but rather the much larger and more prestigious Massachusetts Institute of Technology Radiation Laboratory. Presumably a moonshot was not part of its remit, but Robert Buderi, in his 1996 book on the MIT Rad Lab, The Invention that Changed the World, considered its not having done so a sufficient violation of expectation as to require a 4-page detour from the main topic of his book to describe Project Diana and this surprising "Army coup."
Less than a month later, on February 6, 1946, a group led by the great Hungarian physicist Zoltán Bay, using an approach quite different from that of the Project Diana team, was able to announce its own successful moonbounce. Did Bay see himself as having been in (and lost) a "space race"? In an oral history conducted in October, 1980, the interviewer (Woodruff T.Sullivan III) addressed the question directly with Bay. His response was that he had been sure others were working on moonbounce projects and his suspicion had been that his main competitors were "the Americans"--but he had no idea who they were or how close they migh be to their goal. Despite British primacy in radar research, he did not think the UK was in the running--their efforts had been too keenly focused on the very practical needs of winning the war. Bay actually learned of the success of Project Diana a few days before he made his own successful attempt.
The complementary achievements of Project Diana and Bay's successful moonbounce efforts were summarized as follows by Louis Brown in his 1999 volume A Radar History of World War II: "These two experiments introduced two important techniques that were to make radar astronomy a valuable method for studying the solar system. DeWitt and Stodola showed how sensitive the observations were to Doppler shifts, and Bay showed the power of integration. The later combination of sharp time resolution, Doppler shift and signal integration would evolve into a technique that would provide remarkably accurate topographic maps of the surfaces of Venus and asteroids, but long before such sophisticated results could be admired, radar astronomy determined with great accuracy the astronomical constant, the distance scale of the solar system."
Once the Project Diana team and Zoltán Bay had shown the world that it could be done and how to do it, moonbounce was quickly adopted and adapted for both civilian and military purposes.
Australians Frank Kerr and Alex Shain, puzzled as to why the echoes recorded by DeWitt‘s team had behaved so erratically and suspecting it might well be an ionospheric effect, or even caused in interplanetary space by streams of charged particles shot from the sun, began a series of moonbounce experiments at a newly established field station at Hornsby Valley near Sydney in 1946. By 1947-48, they were conducting not just a demonstration project as DeWitt and Bay had carried out but an extended series of experiments designed to investigate the ionosphere parametrically.
By 1948, with the Cold War well underway, a Naval Research Laboratory engineer named James Trexler figured out that signals emanating from one location (e.g., in Russia) could potentially be intercepted via bistatic transmission to other locations (e.g., in the US) if they happened to bounce off the moon (either accidentally or during brief intervals of "target practice")--a possible solution to the thorny problem of how to monitor Russian ballistic missile testing in an era when flights over the Soviet Union were prohibited. Thus was born the highly classified PAssive MOon Relay or PAMOR, code-named "Joe." Initial tests proved so promising that the project was intensified, at even deeper levels of secrecy. As one wag put it, “Leave it to the US Navy to weaponize the moon.” The military importance of moonbounce was further enhanced in 1954 by the introduction of two-way moonbounce communication.
Then, in October of 1957, the Soviet Union launched the world's first artificial satellite, Sputnik 1, followed 3 months later by the United States' artificial satellite the Explorer. By the mid 1960s a skyful of artificial satellites designed specifically for both military and civilian communications rendered military moonbounce obsolete, and moonbounce became (and remains) largely the province of amateur radio enthusiasts. But moonbounce as pioneered by Project Diana directly prepared the way for missile defense systems, radio communication with spacecraft, and remote mapping of planetary surfaces, and indirectly for uncrewed and even later for crewed moon missions. The moon was no longer shrouded in mystery; Project Diana and other postwar radar researchers brought it into the world of science and technology.
Had not the exigencies of World War II intervened...
...Wilhelm Stepp might have followed up on his group's accidental moonbounce findings and eventually realized that the "perturbations" they regarded as a nuisance had communications potential at least as important as the use of radar for detecting nautical invaders.
...Jack DeWitt, with his unique combination of skills in broadcast communications and radar technology, might have upped his game equipment-wise and followed up on his failed moonbounce attempt in May of 1940 long before he got the chance to pursue his dream for a second time in 1946 (though he would have had to make do without the insights of Edwin Howard Armstrong on receiver sensitivity, the expertise in moving target detection of King Stodola, and the sophisticated mathematical skills of Walter McAfee).
...Zoltán Bay might not have had to reconstruct his lab in war-torn Hungary not once, not twice, but three times before reaching his goal.
Any one of them, and possibly others as well, might have earned the distinction of being the first-ever EME communication. History is full of might-have-beens. As King Stodola put it when interviewed in October, 1979, "[A]s far as I know, [Project Diana] really was the first time that man had in a measurable way manifested his influence beyond the reaches of the immediate locale of the earth. Indeed, somebody on the moon could have received radio signals that were transmitted from the earth, but this was really the first proof of it. And rather interestingly, other people were working on it, too, and several others succeeded--but we, by circumstance or whatever, were the first."
Another radio specialist to recognize this possibility early on was the American Jack DeWitt--a ham radio operator and founder of Nashville, Tennessee's first radio broadcasting station, as well as a skilled astronomer—who wrote in his notebook on May 21, 1940, “It occurred to me that it might be possible to reflect ultrashort waves from the moon. If this could be done it would open up wide possibilities for the study of the upper atmosphere.” But while Bray and Piddington were still pondering the possibility of moonbounce, Dewitt was not merely theorizing; as it happened, the day before he made this notebook entry, he had actually launched a serious though unsuccessful attempt to bounce 2-meter radio waves off the moon. Undaunted, he attributed his failure to lack of receiver sensitivity and remained supremely confident that with additional refinements of his equipment he could succeed. Before he had a chance to try again, however, the US entered World War II, and he joined the Army Signal Corps.
In an odd quirk of history, a few accidental moonbounces were observed in 1943-44 by a group from Telefunken led by Wilhelm Stepp, whose assignment was to develop a system for detecting near-ground targets (ships, vehicles, low-flying aircraft). One of his technicians, Willi Thiel, told him about a strange perturbation he had observed the day before that he could not explain, which gradually subsided after a couple of hours. Stepp was able to repeat the observation: "The fault happened only when the antenna beamed east, disappeared at once after larger changes of the bearing and appeared with a two seconds delay when beaming east again. It seemed we targeted the moon behind the clouds." Soon afterwards the system was turned over to the German military; no further study of the phenomenon was carried out.
Shortly after the War, Stepp returned to graduate school and wrote his dissertation on his theoretical and experimental work in radar--burying in a footnote a single sentence about the unplanned moonbounces. He also mentioned his observations casually at a couple of professional conferences. Some three decades later, in 1974, he published the only report of the finding to appear in the scientific literature, a brief notice in an obscure nautical journal, crediting Thiel with the discovery and providing a few technical details. His modesty was probably at least in part a tacit acknowledgment that he had not recognized the most important aspect of the feat, its communications potential. Still, just enough information about these chance observations surfaced over the years to rescue them from the dustbin of history and to elicit a few snarky remarks about primacy.
It was only with the end of World War II that research specifically intended to prove that the earth's atmosphere could be penetrated, and to investigate the potential of bouncing radio waves off the moon not only for defense purposes but for applications such as communications and radar astronomy, got underway. The field was developing so explosively that groups sprung up more or less simultaneously and independently, without necessarily knowing much about what other such groups were doing.
Project Diana, under the leadership of the same Jack DeWitt who had tried and failed to shoot the moon in 1940, was the first of these purpose-driven efforts to succeed, on January 10, 1946. Interestingly, because the heavy and ungainly Project Diana antenna could not be tilted but only rotated in azimuth, it was subject to the same time limitations as the Telefunken group had noticed: Moonshots could only be attempted twice a day, usually at moonrise but occasionally at moonset, during the 40-minute window that opened when the moon passed through the 15-degrees-wide beam of the antenna pattern.
The pre-eminent radar research group in the United States at the time was in fact not the little Army Signal Corps team in Belmar, New Jersey but rather the much larger and more prestigious Massachusetts Institute of Technology Radiation Laboratory. Presumably a moonshot was not part of its remit, but Robert Buderi, in his 1996 book on the MIT Rad Lab, The Invention that Changed the World, considered its not having done so a sufficient violation of expectation as to require a 4-page detour from the main topic of his book to describe Project Diana and this surprising "Army coup."
Less than a month later, on February 6, 1946, a group led by the great Hungarian physicist Zoltán Bay, using an approach quite different from that of the Project Diana team, was able to announce its own successful moonbounce. Did Bay see himself as having been in (and lost) a "space race"? In an oral history conducted in October, 1980, the interviewer (Woodruff T.Sullivan III) addressed the question directly with Bay. His response was that he had been sure others were working on moonbounce projects and his suspicion had been that his main competitors were "the Americans"--but he had no idea who they were or how close they migh be to their goal. Despite British primacy in radar research, he did not think the UK was in the running--their efforts had been too keenly focused on the very practical needs of winning the war. Bay actually learned of the success of Project Diana a few days before he made his own successful attempt.
The complementary achievements of Project Diana and Bay's successful moonbounce efforts were summarized as follows by Louis Brown in his 1999 volume A Radar History of World War II: "These two experiments introduced two important techniques that were to make radar astronomy a valuable method for studying the solar system. DeWitt and Stodola showed how sensitive the observations were to Doppler shifts, and Bay showed the power of integration. The later combination of sharp time resolution, Doppler shift and signal integration would evolve into a technique that would provide remarkably accurate topographic maps of the surfaces of Venus and asteroids, but long before such sophisticated results could be admired, radar astronomy determined with great accuracy the astronomical constant, the distance scale of the solar system."
Once the Project Diana team and Zoltán Bay had shown the world that it could be done and how to do it, moonbounce was quickly adopted and adapted for both civilian and military purposes.
Australians Frank Kerr and Alex Shain, puzzled as to why the echoes recorded by DeWitt‘s team had behaved so erratically and suspecting it might well be an ionospheric effect, or even caused in interplanetary space by streams of charged particles shot from the sun, began a series of moonbounce experiments at a newly established field station at Hornsby Valley near Sydney in 1946. By 1947-48, they were conducting not just a demonstration project as DeWitt and Bay had carried out but an extended series of experiments designed to investigate the ionosphere parametrically.
By 1948, with the Cold War well underway, a Naval Research Laboratory engineer named James Trexler figured out that signals emanating from one location (e.g., in Russia) could potentially be intercepted via bistatic transmission to other locations (e.g., in the US) if they happened to bounce off the moon (either accidentally or during brief intervals of "target practice")--a possible solution to the thorny problem of how to monitor Russian ballistic missile testing in an era when flights over the Soviet Union were prohibited. Thus was born the highly classified PAssive MOon Relay or PAMOR, code-named "Joe." Initial tests proved so promising that the project was intensified, at even deeper levels of secrecy. As one wag put it, “Leave it to the US Navy to weaponize the moon.” The military importance of moonbounce was further enhanced in 1954 by the introduction of two-way moonbounce communication.
Then, in October of 1957, the Soviet Union launched the world's first artificial satellite, Sputnik 1, followed 3 months later by the United States' artificial satellite the Explorer. By the mid 1960s a skyful of artificial satellites designed specifically for both military and civilian communications rendered military moonbounce obsolete, and moonbounce became (and remains) largely the province of amateur radio enthusiasts. But moonbounce as pioneered by Project Diana directly prepared the way for missile defense systems, radio communication with spacecraft, and remote mapping of planetary surfaces, and indirectly for uncrewed and even later for crewed moon missions. The moon was no longer shrouded in mystery; Project Diana and other postwar radar researchers brought it into the world of science and technology.
Had not the exigencies of World War II intervened...
...Wilhelm Stepp might have followed up on his group's accidental moonbounce findings and eventually realized that the "perturbations" they regarded as a nuisance had communications potential at least as important as the use of radar for detecting nautical invaders.
...Jack DeWitt, with his unique combination of skills in broadcast communications and radar technology, might have upped his game equipment-wise and followed up on his failed moonbounce attempt in May of 1940 long before he got the chance to pursue his dream for a second time in 1946 (though he would have had to make do without the insights of Edwin Howard Armstrong on receiver sensitivity, the expertise in moving target detection of King Stodola, and the sophisticated mathematical skills of Walter McAfee).
...Zoltán Bay might not have had to reconstruct his lab in war-torn Hungary not once, not twice, but three times before reaching his goal.
Any one of them, and possibly others as well, might have earned the distinction of being the first-ever EME communication. History is full of might-have-beens. As King Stodola put it when interviewed in October, 1979, "[A]s far as I know, [Project Diana] really was the first time that man had in a measurable way manifested his influence beyond the reaches of the immediate locale of the earth. Indeed, somebody on the moon could have received radio signals that were transmitted from the earth, but this was really the first proof of it. And rather interestingly, other people were working on it, too, and several others succeeded--but we, by circumstance or whatever, were the first."