Menzel, Donald Howard

views updated May 21 2018


(b. Florence, Colorado, 11 April 1901; d. Cambridge, Massachusetts, 14 December 1976),

astronomy, theoretical astrophysics, solar physics, gaseous nebulae.

Menzel was one of the first American astronomers to place modern physics at the core of astrophysical practice. He used quantum physics to study the nature of gaseous nebulae; the solar atmosphere, chromosphere, and corona; and also to explore the structure of the atom itself. He founded two solar observatories and was a major broker in international astronomy at midcentury. He achieved popular notice as an author of astronomical themes, nature studies, and science fiction, but most widely as a critic and skeptic of efforts directed to the study of unidentified flying objects and the nature of their occupants.

Early Life and Training . Menzel was a grandson of a Civil War veteran who settled in Denver, Colorado. Menzel’s father, Charles Theodor Menzel Jr., worked as a railroad clerk and ticket agent in Florence, Colorado, where Menzel was born, and then moved his family to the remote town of Leadville, where he became a station manager. Menzel spent his early childhood under rather difficult conditions. By 1910, however, his father had saved enough money to purchase a mercantile company and store in Leadville and the family prospered.

His mother, Ina Grace Zint, managed the growing family, and maternal grandmother, Hattie Prince Zint, looked after the children’s training, encouraging in particular the water coloring and woodburning arts. They were a serious Lutheran family, devoted to learning. His parents tried unsuccessfully to enter Menzel in public school before he was old enough, and when their application was rejected, his father got him a library card and encouraged reading. Menzel relished the science fiction of the day, including in particular Jonathan Swift’s Gulliver’s Travels, Jules Verne’s books, and Johann David Wyss’s Swiss Family Robinson. He was fascinated by the scientific questions raised in this literature.

Menzel identified with a small group of boys who engaged in general roughhousing, which prompted his father to teach him how to box, and Menzel was eventually accepted as a boy who could defend himself. He continued to pursue reading, and even wrote a prize-winning poem, “The Little Stars,” which convinced him he had a future as a writer. He played chess, learned Morse code, and built radios, and was an avid rock and mineral collector, eventually using his accumulated treasures as a means of income through selling iron pyrite, galena, and blue-lead sulfide to tourists. Drawn by his father to the railroad, Menzel was able to ride local trains of various sorts; he remembered in particular his rides through Fremont Pass, where his first large solar observatory was built many years later.

Menzel was a fast learner and precocious student. He graduated high school at age sixteen after the family had moved to Denver in 1915 and entered Denver University in 1917, graduating from there in only three years. He majored in chemistry but also pursued astronomy, especially after viewing a solar eclipse in 1918, and then a bright nova outburst. Herbert Howe, professor of mathematics and astronomy and also dean of the College of Liberal Arts, befriended Menzel, eventually granting him access to the 20-inch (59-centimeter) refractor at Chamberlain Observatory. Although he declared for chemistry, Menzel loved astronomy and observing variable stars. Through another member of the Denver faculty, Menzel came into contact with Raymond Smith Dugan of Princeton University, a leading variable star observer, and Dugan helped him join the American Association of Variable Star Observers.

Upon graduation Menzel stayed local, entering the graduate school and obtaining a master’s degree in one year in mathematics and astronomy, in the spring of 1921 at the age of twenty. By then he and Dugan had corresponded to the point where Menzel was offered a studentship at Princeton, working for Dugan and required to observe and analyze eclipsing binary star systems. Menzel would be a special student at first, because the director of the Princeton University Observatory, Henry Norris Russell, was concerned that his training thus far had been very narrowly constrained; in spite of his contact with Howe, he was largely self-educated in astronomy.

Graduate Years at Princeton and Harvard . Entering Princeton in the fall of 1921, Menzel quickly mastered Dugan’s visual photometer on the Halsted Observatory’s 23-inch (58-centimeter) refractor, and distinguished himself in his studies. He roomed with the only other astronomy graduate student, Bancroft W. Sitterly, but came into contact with highly competitive students in mathematics and physics.

Coursework under Russell exposed Menzel to the forefront of astrophysics, namely the application of the principles and practices of the modern physicist to the study of astronomy. Russell concentrated on the analysis of physical processes and mathematical shortcuts to their elucidation, which fascinated Menzel. He started studying related fields in physics and mathematics, taking courses and attending lectures by Oswald Veblen, Luther Eisen-hart, and Henry Fine. Encouraged by John Q. Stewart, the third member of the Princeton astronomy faculty who held a dual appointment in physics, Menzel studied physical optics and the quantum theory of radiation under Augustus Trowbridge, and eventually Stewart directed

him to explore laboratory experiments on the absorptive properties of sodium as one means of gaining insight that would be useful for studying the chemical compositions of the atmospheres of the Sun and stars.

Through his variable star work and through Russell, Menzel spent a summer at the Harvard College Observatory, working for Harlow Shapley on his surveys of the distribution of nebulae and the distances to the Magellanic Clouds. But his continued exposure to physics, taking courses from Karl Taylor Compton in atomic theory in particular, again directed by Stewart, wedded him to astrophysics. He was therefore poised to take advantage of an extraordinary set of circumstances: the emergence of Meghnad Saha’s ionization equilibrium theory and its mathematical elucidation by Ralph Howard Fowler and Edward Arthur Milne, as well as by Russell and Stewart, and the presence of an enormous cache of spectroscopic data at Harvard that was ripe for further analysis in light of this new theory. Russell accordingly sent Menzel to Harvard for his third graduate year 1923–1924, to exploit this material, specifically to measure line intensities to calibrate the Harvard classification sequence of stellar spectra to a physical temperature scale.

Menzel soon found that he was not alone in the Harvard plate stacks. The British scholar Cecilia Payne was ardently pursing the same questions. After a period of adjustment, they both exploited the collection effectively. Menzel wrote up his findings, analyzing arc line spectra for metals for which Russell had series relations.

During his graduate school years at Princeton, Menzel came into contact with Hugo Gernsback and eventually began writing popularly, his work appearing in Gernsback’s pulp Amazing Stories. Menzel suspected, correctly, that such activities were frowned on. He managed to hide the extent of his writing by using pseudonyms. His writing for Amazing Stories apparently did not begin until he had his PhD and was bound for his first position.

Lick Observatory . It is not clear why Menzel took a teaching position at the University of Iowa; certainly this was not the sort of position Russell would have recommended if he had high hopes for his graduate student. Menzel recalled offers from Gernsback to become an associate editor of Amazing Stories, a standing offer from Denver and from various high schools, and said only that he chose Iowa because it offered a decent salary and the promise of time and opportunity for research. But after a year teaching at the university, and a short appointment at Ohio State University, he became dissatisfied and contacted Russell for advice. Now Russell acted promptly, supporting Menzel’s candidacy for a junior position at the Lick Observatory, operated by the University of California, a position Menzel obtained without difficulty.

Russell was anxious to have his student at Lick so that he would have access to its marvelous observational resources, including photographic records from many solar eclipse expeditions such as flash spectra that held the key to the structure of the solar reversing layer, the region where its absorption spectrum originated. Menzel accordingly arrived at Lick, and Russell directed his attention to this cache of material. By 1930 Menzel had revolutionized knowledge of the solar atmosphere and its chromosphere.

Although Lick was a great mountain observatory, it was a classic astronomical institution, where careers were narrowly defined by instrumentation and the will of the director. Menzel, trained under Russell, believed in broader professional vistas and chafed at the many chores he was expected to handle. He even felt his monumental work on the solar atmosphere was poorly received by Lick astronomers, especially when they advised him not to publish the theory portion in his observatory monograph, an extensive discourse on his application of wave mechanics, but to reserve it for some appropriate journal that entertained such fuzzy stuff. As Robert Grant Aitken wryly advised him, Lick was an “Observatory!” where data were collected and recorded. “Leave the theory to the poor, underprivileged British astronomers,” Aitken quipped, “such as Milne and Eddington, who don't have an observatory” (Menzel unpublished autobiography, pp. 210, 222–223). Menzel often recalled this quip many years later, but at the time, it was demoralizing. Menzel found the faculty on the Berkeley campus far more collegial, and spent as much time there as he could, teaching fine students, and attracting some of them, including Fred Whipple, to do their thesis work at Lick. He also sought escape in his continued clandestine writing for Gernsback.

Move to Harvard . Menzel had managed to secure a junior position for Whipple at Harvard in 1931, and remained in contact with Shapley. When Harry Plaskett left Harvard for Oxford in 1932, Russell, knowing of Menzel’s unhappiness at Lick, suggested Menzel as Plaskett’s replacement. Arriving at Harvard on 1 September 1932, one day after he had helped observe a solar eclipse from Fryeburg, Maine, as his last duty for Lick, Menzel brought to Harvard a considerable cache of data on planetary nebulae spectra that he now hoped to exploit. He had already written on physical processes in gaseous nebulae in his last months at Lick Observatory, but it needed further physical analysis and discussion. He collaborated with Joseph Boyce, whom he had come to know at Berkeley but who was now at the Massachusetts Institute of Technology (MIT), as well as with Payne, and through the 1930s continued research along two related lines: gaseous nebulae and the outer regions of the solar atmosphere.

Menzel had been fascinated by the source of the illumination in nebulae since 1926 when he suggested, but then rejected, the possibility that the emission lines of the hydrogen Balmer series seen in nebulae were the result of photoionization and recombination caused by ultraviolet radiation from the central stars. Nevertheless, Menzel continued his interest in the causes of nebular illumination and formed a series of collaborations and group studies at Harvard on physical processes in gaseous nebulae, engaging bright students such as Lawrence Aller, James Baker, Leo Goldberg, and others. Starting in 1937 and lasting through 1945, he led studies that were the first to systematically blend observational data and wave theory to calculate temperatures, electron densities, and compositions in planetary nebulae, in terms of derived temperatures of the stars responsible for illuminating the gas. This work, expressed in a series of eighteen papers, helped to establish the careers of his finest students.

Throughout the decade, Menzel became a member of Shapley’s senior staff, along with Bart Bok, Payne, and Whipple. In the mid-1930s Shapley promoted Menzel to associate professor and tenure. Menzel also engaged in high-profile eclipse expeditions. Most significant was an international effort to observe the Siberian eclipse of 1936, for which he developed, in conjunction with MIT physicists, a set of large high-dispersion spectrographic devices made of a lightweight magnesium alloy. He also secured technical assistance and support from the Dow Chemical Corporation, the Folmer-Graflex Company, and Bausch & Lomb, and invited a team of radio physicists from the Cruft Physics Laboratory to examine the effect of the eclipse on the Heaviside layer, using radio transmitters and receivers placed in proximity to the station within the path of totality. Menzel was thus the first astrophysicist to collect optical and radio phenomena to explore how solar activity controlled the Earth’s ionosphere. This goal led to his western expeditions and the establishment of two major solar observatories.

Menzel shared the astronomers’ dream of observing the solar corona at will, not having to wait for the occasional solar eclipse. The need to record continuous variations in solar activity and to correlate these to earthy atmospheric phenomena was becoming the most obvious practical application of astronomy since the rise of celestial navigation. In 1935 he approached the U.S. Department of Agriculture with a proposal to apply coronal studies to search for links between solar activity and weather, beyond what he thought mere sunspot numbers or even the controversial solar constant correlations produced at the Smithsonian Astrophysical Observatory (SAO) could show.

In 1930 Bernard Lyot’s new invention, a corona-graph, showed that one could photograph the solar corona outside an eclipse, under the pristine conditions of the Pic Du Midi Observatory in the Pyrenees. Menzel’s proposal, however, was to create an electronic version he called a Coronavisor that would subtract skylight and photospheric glare electronically. Following the ideas of A. Melvin Skellett of the Bell Telephone Laboratories, and not in any way reminiscent of Lyot’s simple photo-optical design, Menzel did not think it was necessary to observe from a high, dry altitude where scattered light would be minimized. His proposal was funded, but progress was slower than hoped, and though he was clear in his intentions, to build a physical laboratory at Harvard’s Oak Ridge observing station some 30 miles (48 kilometers) west of campus specifically for the study of solar terrestrial relations, by late 1937 the grant had been expended and there was nothing tangible to show for the effort. Only then did he apply Lyot’s designs, and begin thinking of a western observatory.

Menzel asked his student Baker to design and build the lenses, and engaged the talents of Brian O’Brien’s staff at the University of Rochester Institute of Optics as well as the expertise of the PerkinElmer Corporation and the collegiality of Lyot. He planned to take his instrument to Lick Observatory, but delays and his search for sites that at least matched Lyot’s drew him eventually back to his mountain home and a site near Leadville, which he found in 1939 on hikes with his father.

When government support ceased in 1939, Menzel had to let his staff go, and turned to a young graduate student, Walter Orr Roberts, to continue the work. Roberts had worked at Kodak for C. E. Kenneth Mees and had interests that closely meshed with Menzel's. By the spring of 1940, a 4-inch (10-centimeter) instrument was being tested at Oak Ridge and was bound for installation at Climax, Colorado, at some 11,500 feet (3,505 meters) elevation, with much of the construction support provided by the Climax Molybdenum Company, after Menzel appealed to them for help. Over the summer, the station was built, and by the end of the summer, the first photographs of prominences by Roberts gave great hope that success was near. It would take another year, to October 1941, before the corona was captured. Roberts was the one who did it, while Menzel remained the enabler, faced with constant funding problems. But soon, Menzel went to war, and found an eager new funder.

War Work . In its first half-year of operation, the Climax station had secured evidence linking coronal activity to subsequent ionospheric storm activity on Earth. This and intelligence reports hinting that the Germans were building an ionospheric monitoring network using corona-graphs soon led the National Defense Research Committee to fund Climax. Throughout the war, Climax data were sent directly to the National Bureau of Standards for analysis. Menzel, at the center of making all this happen, remained at Harvard as he entered war work late in the year.

Menzel’s first project, an Office of Scientific Research and Development (OSRD) contract, was to design and build optical gun sights devices for tracking aircraft that were using the Sun for cover, exploiting his experience with coronagraphs. But he also enrolled in a navy correspondence course in cryptanalysis, the result of a lingering childhood fascination with ciphers and codes and the knowledge that such skills were needed. Menzel had already studied cryptology when he was at Berkeley, fascinated through chance contacts with others taking these courses, and later came to know Howard Engstrom, who would join the Washington office of the Chief of Naval Communications. In 1941, Menzel’s ability to rapidly and creatively complete coding assignments impressed the navy, which by September asked him to take part in training women at Radcliffe College and other seven-sister colleges. This program soon extended to Harvard graduating seniors and in all several hundred students received training and eventual commissions in the navy. He was in the midst of this activity when, in the fall of 1942, he was commissioned a lieutenant commander and assigned to the Office of the Chief of Naval Communications, after one month of intensive training and indoctrination in a secret program on the Harvard campus. In Washington, however, his responsibilities extended to the theory of radio wave propagation and exploited his knowledge of solar physics, cryptanalysis, and his experience and fascination for shortwave ham radio. He soon met the navy’s expectations by finding ways to match radio frequencies to ionospheric conditions, primarily to facilitate the detection of enemy submarines.

Serendipitously aligned with the program he set in place at Climax and the National Bureau of Standards, Menzel was now on active duty using the solar observations to predict changes in radio communication conditions and thereby to create a system of managing operational radio frequencies. Eventually he commanded a section that kept records of all naval radio messages, both friendly and intercepted, and collaborated with the National Bureau of Standards and the Department of Terrestrial Magnetism of the Carnegie Institution of Washington to produce comprehensive data sets for the transmission characteristics of the atmosphere as a function of time. Menzel was also directed to join various Wave Propagation committees of the Joint and Combined Chiefs of Staff, and he ultimately chaired these national and allied efforts to maintain coordinated research in the subject and promote the systematization of radio fade-out predictions.

Menzel also contributed to extending the effectiveness of radar countermeasures, mainly to obtain a better understanding of anomalous propagation phenomena that could confuse radar intelligence and techniques for submarine direction finding and communications. After developing the theory and practical methods of identification, he tested them under operational conditions in Panama. Menzel later recalled that it was experience gained in these circumstances that led him to become one of the most vocal and visible debunkers of reported UFO phenomena, a duty he relished. At the end of the war Menzel prepared an “Elementary Manual of Radio Propagation” that in 1948 was published commercially.

In the closing months of the war Menzel turned back to issues relating to ship communications and code breaking, but he and others also began to sense that a shakedown was likely to come among the various services in the postwar world for control of wave propagation responsibilities. In concert with Edward Uhler Condon, then the director of the Bureau of Standards, as well as J. Howard Dellinger, director of the Interservice Radio Propagation Laboratory within the bureau, Menzel outlined the need for an agency that could provide systematic services after the war. His outline included a worldwide network for ionospheric and weather data gathering and a centralized facility for processing the information. The proposal— and a multimillion dollar annual budget—were approved up the line, and resulted in the establishment of the civilian Central Radio Propagation Laboratory (CRPL) of the National Bureau of Standards, as of 2007 located in Boulder, Colorado.

Menzel recalls being asked by Condon at war’s end to take over the direction of the CRPL, as Dellinger was soon to retire. He was tempted, to be sure, but he was also aware of what his new expertise could mean to astronomy, especially radio astronomy. The fact that the Sun emitted a complex radio signature had been carefully guarded during the war, but the release of such information in peacetime would be explosive. Menzel was also keenly aware of the possibility of using shortwave radar to bounce signals off the Moon, and what this might mean not only for communications but for improving knowledge of the lunar orbit. Though he arranged for several conferences of navy astronomers and communications personnel, nothing came of these suggestions at the time. What was clear to Menzel, apparently, was that he might best exploit his newly found knowledge, expertise, and military and government contacts as a Harvard professor, and not an active duty officer. In any case, he returned to Harvard but remained a special consultant for the CRPL and remained active in both military and civilian Washington circles in other capacities for the rest of his career. In addition to the offer from Condon, Menzel had other offers from the Naval Electronics Laboratory and from associates planning to develop electronic computers. As a consultant, Menzel found his work on behalf of the CRPL especially engrossing, allowing him to suggest major changes, such as the removal of the CRPL from Washington in favor of Boulder, Colorado, near a university and in the comparative proximity of his High Altitude Observatory (HAO) at Climax. The University of Colorado was ready to provide assistance, facilities, and joint appointments to the CRPL, and also offered the advantage of graduate student manpower. Gaining the approval of locals as well as Washington, Menzel remained intimately involved in the design and construction of the CRPL over the years, becoming as well an honorary member of the Boulder Chamber of Commerce. He was also an active member of the National Bureau of Standards Visiting Committee.

Postwar Institution Building . Menzel and much of the Harvard College Observatory staff returned to their prewar positions under conditions that can only be described as highly polarized. Menzel and Whipple, especially, had experienced vastly wider horizons made possible through

the application of new technologies and government funding. Other members of the Harvard senior staff, mainly Shapley, Bok, and to some extent Payne (Payne-Gaposchkin after her 1934 marriage to the Harvard astronomer Sergei Gaposchkin), were wary of government intervention, and especially resisted military funding. But by the late 1940s, they all keenly knew that what they needed was a major infusion of new support, if only to maintain what they had built as a competitive facility for teaching and research.

There was also significant friction between Shapley and the Harvard administration, mainly with President James Bryant Conant. In an attempt to normalize the observatory and to reduce the director’s autonomy, in 1945 Conant created the Harvard College Observatory Council (HCOC), consisting of senior staff and the director. Among the members of the HCOC, Menzel was much closer to the Harvard administration than Shapley, especially to Dean Paul Buck. He represented modern lines of activity and closer ties with campus departments than Shapley or the others. In a series of reorganizations in the late 1940s, prompted by the Harvard administration, Buck designated Menzel as chairman of the Department of Astronomy, responsible for coordinating the teaching load. Shapley countered by designating Bok as associate director and his implied successor, but soon Menzel was designated associate director for solar research. Menzel recalls that Shapley was infuriated by all this, but the actual series of events, and their intent, remained unclear. In any event, the HCOC approved this reorganization because it did distribute chores more equitably.

Immediately after the war, Shapley and the HCOC agreed that the observatory needed a major infusion of funds and planned a campaign. Conant, however, blocked Shapley’s fundraising efforts in the mid-1940s, in preference for a combined Harvard campaign. These steps virtually ensured that the observatory would be in crisis at Shapley’s retirement, which was due in September 1952, and was being enforced by Conant. Tensions rose again in 1950, when Conant and Buck asked the observatory to consider becoming a regular campus department, placing the directorship of the observatory and chairmanship of the department on a rotating cycle. Shapley and the HCOC firmly rejected this idea, but they all knew that deep changes were afoot.

In 1951 Shapley and the HCOC pleaded with the administration to choose a successor expeditiously. Instead, Conant asked J. Robert Oppenheimer, as a member of the Board of Overseers, to convene a blue-ribbon panel of physicists and astronomers to assess Harvard astronomy. With Shapley’s retirement in September 1952, Buck asked Menzel to be acting director, prompting Bok to resign as associate director. The HCOC remained, but there was great tension throughout the observatory. While the committee deliberated, Shapley’s people, including Bok and much of the junior staff, were clearly at odds with Menzel and Whipple, and it became Menzel’s job not only to get the HCOC working again, but to satisfy the complaints of the committee.

Menzel immediately began a series of reforms in line with the desires of the Harvard administration, condemning buildings that had fallen into disrepair, giving notice to groups within Shapley’s extended observatory family, such as the American Association of Variable Star Observers, that they had to move out of the observatory, culling and regularizing the observatory library book holdings, and, most sensitive of all, culling the famed Harvard photographic plate collection and divesting Harvard’s interest in its southern station at Bloemfontein in South Africa. At the same time, less controversial to the rank and file, Menzel was also taking steps to divest Harvard of any financial responsibility for the HAO in Colorado, in favor of a new station at Sacramento Peak in New Mexico, in proximity to air force and army ordnance missile testing facilities near Alamogordo and White Sands, New Mexico.

Menzel’s New Mexico project was originally an attempt to seek out a complementary observing site to HAO for fuller seasonal coverage. HAO had been officially incorporated in 1948 as an independent organization affiliated with Harvard and the University of Colorado, managed by Menzel’s former student Roberts. In the postwar world, with the relaxation of wartime pressures and reductions in wartime funding, and with Conant’s restrictions on Harvard campaigns for financial support in favor of his central university effort, Menzel was frustrated, maintaining Climax with private donations. Thus in his retrenchment campaign, Menzel included Climax. Beyond funding problems, there had been another deeply fractious issue.

In the spring of 1950, responding to what later were revealed to be accusations by Colorado businessmen, two air force officers presented Menzel with charges of disloyalty that could result in the revoking of his security clearances, and all employment as consultant to the air force, which included Sacramento Peak. The air force was funding Sacramento Peak, facilitated by Menzel’s close relationship with the air force Cambridge Research Laboratories, within the Air Materiel Command. This facility was just being built, with John W. Evans and Roberts tasked to provide scientific direction and improved instrumentation, when Menzel’s loyalty hearings started in Boston. These hearings took place between late May and early June 1950, but deliberations dragged into 1951, when Menzel was finally exonerated after enlisting Harvard lawyers and an impressive list of staunch backers with Washington connections. But the whole affair tested Menzel’s relations with Roberts and the Colorado businessmen. In fact, Roberts was also investigated for alleged subversive activities, mainly his public lectures and addresses.

By October 1952, freshly installed as acting director and faced with the challenge of bringing the observatory and its far-flung assets into line with Harvard policies, Menzel was writing critical letters to Roberts regarding his management of HAO. He accused Roberts of being more focused on production than good research and asserted there was a lack of good supervision overall. Evans was now at Sacramento Peak full time, and Roberts was encountering serious cost overruns building new instrumentation. In March 1953, Menzel alerted Buck to problems at Climax, and how these were drawing the critical attention of other solar astronomers such as Robert R. McMath and Leo Goldberg at Michigan. By October 1954, formal relations between the two observatories ceased, though Menzel expressed the hope that they would still be loosely linked through a wide consortium he called the Solar Associates.

Directorship of HCO . Even though Menzel was made acting director, he was not originally in line for the directorship. The Oppenheimer committee did not regard any of the remaining faculty to be capable of restoring Harvard astronomy to the front ranks, and even considered among other options closing all the observing stations and creating a wholly new department that would take the forefront in theoretical astrophysics. With the committee’s initial report on the state of astronomy in hand by the end of 1952, Conant then asked Oppenheimer to search for a new director, and this took another full year, as he and Harvard administrators negotiated first with Bengt Strömgren, then with Jan Oort, and finally, equally unsuccessfully, with Otto Struve. During the year, Menzel’s actions in revamping the observatory, making it more responsive to campus standards, improving the infrastructure through cutbacks and efficiencies, more than impressed the administration. In the spring Payne-Gaposchkin wholeheartedly supported Menzel, writing to Buck that under Menzel’s leadership there was now more solidarity and cohesion than division, that Menzel was taking steps to broaden and strengthen astrophysics and, most importantly, that he was improving relations with Harvard campus departments such as physics and chemistry, and the applied sciences at MIT. Cross-field research was then an important buzzword for the Harvard administration, and Payne-Gaposchkin used it deftly in her promotion of Menzel. Endorsements such as these led to Menzel’s appointment in January 1954, initially for a five-year period.

As director, Menzel set about consolidating relations with Sacramento Peak, improving the Oak Ridge Station, mainly through supporting Bok’s development of a radio telescope there. Menzel also took the initiative to bring the Smithsonian Astrophysical Observatory (SAO) to Harvard in 1955. Menzel was among those the new Smithsonian Secretary Leonard Carmichael turned to for advice about the future of the SAO, which had been in Washington, DC, for more than a half-century but had fallen behind the front ranks in modern astrophysics, concentrating solely on monitoring the Sun’s output of energy. After deliberating options, which included moving SAO to Colorado to be part of HAO, Carmichael decided that the best route to take would be to associate SAO with a major university, and Menzel stepped in to suggest Harvard, eventually with Whipple as the SAO director. At the time, the SAO had dwindled to an observatory virtually in name only. What both Menzel and Whipple realized was that by bringing the SAO association to Harvard, they were opening up a new route to government funding at a time when this type of support was rapidly increasing. The Smithsonian had considerable resources and also provided a mechanism to bring classified work to Harvard, or so thought McGeorge Bundy, who had replaced Buck as dean of the faculty when Conant departed and Nathan Pusey was installed as Harvard’s new president. In the spring of 1955 SAO became part of the Harvard College Observatory, and Whipple built up a new staff with programs relating to upper atmosphere studies, meteoritics, and satellite tracking, preparing for the onset of the International Geophysical Year in 1957.

Menzel also enjoyed contact with Senator John F. Kennedy when Kennedy was asked, as a member of the Board of Overseers, to chair the HCO visiting committee in 1958. Through frequent meetings in both Cambridge and Washington over the next several years, Menzel secured Kennedy’s endorsement for expanding HCO facilities, in concert with increased support from the Smithsonian, and also became an informal advisor on science policy.

Although the spectacular growth of the astronomical facilities overall during Menzel’s tenure as director was mainly due to Whipple’s efforts, Menzel managed to make significant improvements to staff and facilities as well, establishing a radio astronomy facility in Fort Davis, Texas, supporting radio studies with the spacecraft Mariner 2, strengthening both experimental and theoretical studies in spectroscopy and atomic physics, and greatly strengthening the teaching and PhD production of the department of astronomy. His most significant hire was to bring Goldberg back to Harvard in 1960 to take over and greatly expand solar physics, mainly through taking a strong role in the Orbiting Solar Observatory mission of the National Aeronautics and Space Administration’s (NASA). Bringing Goldberg back to Harvard was a major accomplishment for Menzel. Goldberg was one of his most capable students and had worked closely with him in one of his most fruitful problem areas: the calculations of the intensities of absorption lines.

Goldberg also shared Menzel’s goal of establishing a truly powerful astrophysical facility in the west, in Hawaii. This dream became one of Menzel’s greatest preoccupations in the last years of his chairmanship. In the early 1960s, Menzel sought to establish a large observatory facility on 13,000-foot (3,962-meter) Mauna Kea. Although he garnered interest from NASA, Menzel was unable to secure the endorsement of the HCOC, which he later recalled as a serious upset at the time. His frustrations, he felt, led ultimately to a heart attack in 1965, at age sixty-four. Menzel endured open-heart surgery and many months of recuperation, and resigned his directorship in favor of Goldberg, who succeeded him in 1966. Menzel retired in 1970.

Menzel married Florence Kreager in 1926; they met during Menzel’s brief tenure teaching at Ohio State, where she was a student. Florence proved to be an important asset at the Lick Observatory; her sociability and grace helped to make the serious Menzel more acceptable to the close-knit Lick staff and students alike. She continued to be even more open and accessible to students and junior faculty at Harvard and was remembered fondly by many of Menzel’s associates. They had two daughters, Suzanne and Elizabeth.

Although his most cited works remain his contributions to physical processes in gaseous nebulae, and his devotion to both observational and theoretical astrophysics remain among his most lasting legacies, Menzel is most popularly remembered in the early twenty-first century as a tireless debunker of the UFO phenomenon, a subject he wrote on frequently and never ceased to disparage. He is also remembered by colleagues, students, and casual astronomy enthusiasts alike for his indefatigable efforts to observe solar eclipses worldwide and to enthuse about them and other sky-watching activities through his popular writing, which continued throughout his career. His interests always ranged far beyond the strict bounds of astronomy and included radio propagation, communications problems, radio electronics, and electronic intelligence, specifically navy efforts known collectively as electronic intelligence (ELINT). In retirement, he continued to offer his services to both the military and to industry interested in electronic communications systems and technologies. In 1973 he became scientific director of Electronic Space Systems Corporation (ESSCO), a defense electronics and communications company in Concord, Massachusetts, known for manufacturing radomes and radio telescopes.


The bulk of Menzel’s professional papers are contained in Donald Howard Menzel, 1931–1986 HUG 4567 at the Harvard University Archives, Pusey Library, Cambridge, Massachusetts. Also at Harvard are his records as HCO director, and related collections, including Records of the Harvard College Observatory (UAV 630.37.x), Records of the High Altitude Observatory (UAV 631.10.x), and Records of the Dept. of Astronomy (UAV 169.12.x). He deposited his records dealing with UFO phenomena at the American Philosophical Society, and his files covering his loyalty hearings and potential loss of security clearance are housed at the University of Denver.


With William W. Coblentz and Carl O. Lampland. “Planetary Temperatures Derived from Water-Cell Transmissions.” Astrophysical Journal 63 (1926): 177–187.

“The Planetary Nebulae.” Publications of the Astronomical Society of the Pacific 38, no. 225 (1926): 295–312.

“Pressures at the Base of the Chromosphere: A Critical Study of Milne’s Theories.” Monthly Notices of the Royal Astronomical Society 91 (1931): 628–652.

“Crocker Eclipse Expedition to Fryeburg, Maine: Report on the Jumping-Film Spectrographs.” Publications of the Astronomical Society of the Pacific 44, no. 261 (1932): 356–358.

With Joseph C. Boyce and Cecilia H. Payne. “Forbidden Lines in Astrophysical Sources.” Proceedings of the NationalAcademy of Sciences of the United States of America 19, no. 6 (1933): 581–591.

With Henry Norris Russell. “The Terrestrial Abundance of the Permanent Gases.” Proceedings of the National Academy of Sciences of the United States of America 19, no. 12 (1933): 997–1001.

With Chaim L. Pekeris. “Absorption Coefficients and Hydrogen Line Intensities.” Monthly Notices of the Royal Astronomical Society 96 (1935): 77–112.

With Henry Norris Russell and Cecilia H. Payne-Gaposchkin. “The Classification of Stellar Spectra.” Astrophysical Journal 81 (1935): 107–118.

“The Theoretical Interpretation of Equivalent Breadths of Absorption Lines.” Astrophysical Journal 84 (1936): 462–473.

With Leo Goldberg. “Multiplet Strengths for Transitions Involving Equivalent Electrons.” Astrophysical Journal 84 (1936): 1–10.

“Physical Processes in Gaseous Nebulae. I.” Astrophysical Journal 85 (1937): 330–339. With different coauthors, many of them his students, Menzel published eighteen papers in this series between 1937 and 1945.

With Leo Goldberg. “The Solar Corona and Ultraviolet Radiation.” In Centennial Symposia, December 1946: Contributions on Interstellar Matter, Electronic and Computational Devices, Eclipsing Binaries, [and] the Gaseous Envelope of the Earth, 279. Harvard Observatory Monographs, no. 7. Cambridge, MA: Harvard Observatory, 1948.

With R. Grant Athay, JeanClaude Pecker, and R. N. Thomas.“The Thermodynamic State of the Outer Solar Atmosphere V A Model of the Chromosphere from the Continuum Emission.” Astrophysical Journal Supplement 1 (1955): 505.

With R. Grant Athay. “A Model of the Chromosphere from the Helium and Continuum Emissions.” Astrophysical Journal 123 (1956): 285.

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With Bruce W. Shore. “Generalized Tables for the Calculation of Dipole Transition Probabilities.” Astrophysical Journal Supplement 12 (1965): 187.

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With Bruce W. Shore. Principles of Atomic Spectra. Wiley Series in Pure and Applied Spectroscopy. New York: Wiley, 1968.

“Oscillator Strengths, f, for High-Level Transitions in Hydrogen.” Astrophysical Journal Supplement 18 (1969): 221.

With Fred L. Whipple and Gerard de Vaucouleurs. Survey of the Universe. Englewood Cliffs, NJ: Prentice-Hall, 1970.


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David DeVorkin

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