TOUSEY, RICHARD

(b. Somerville, Massachusetts, 18 May 1908;

d. Cheverly, Maryland, 15 April 1997), vacuum ultraviolet techniques in photometry and spectroscopy, optics, solar physics, space science.

Tousey, a laboratory spectroscopist and optical specialist who worked most of his career at the U.S. Naval Research Laboratory (NRL), led a team that was the first to successfully design, build, and fly a spectrograph on a captured German V-2 missile that produced a photographic record of the ultraviolet spectrum of the Sun, never before seen by humans. Tousey remained a central figure active in ultraviolet solar research with rockets, satellites, and human spacecraft throughout his career, and mentored several generations of space scientists.

Born in Somerville, Massachusetts, on 18 May 1908 to Adella Hill Tousey and Coleman Tousey, a dentist, Richard Tousey recalled being especially influenced by his early schooling at what was at first called the Harvard Cooperative Open-Air School and later the Shady Hill School. There he gained a deep fascination and appreciation for nature, which was enhanced by summers at a series of family homes on the Maine shore, where he was encouraged to learn to sail with his brother and sister. His fascination continued through grade schools and was further stimulated by a family friend, John F. Cole, who introduced Tousey to his machine shop and extensive library and took an interest in the astronomical basis for navigation, which he shared with Tousey. Cole helped Tousey build a crystal receiver, learn Morse code, and then learn about vacuum-tube electronics.

Tousey entered Tufts University at age sixteen, the third generation in his family to do so, living at home and supported by his family. His interest in radio steered him into physics courses, but he was not committed to a career at first, ultimately taking a combined physics and mathematics curriculum. Graduating with highest honors in 1928, he entered Harvard University in physics, but still had not acquired any clear goals. He continued to explore options through contact with John Clark Slater and Theodore Lyman, and finally chose experimental physics under Lyman, because Lyman suggested a topic, the reflecting power of metals in the extreme ultraviolet, that encompassed Tousey’s interests in solid-state physics gained under Slater.

Tousey was awarded the MA in 1929, taking courses under Friedrich Hund and Frederick A. Saunders, with whom he shared a strong interest in birding (both were members of the Nuthall Ornithological Club). The PhD came in 1933, and by then Tousey very much followed in Lyman’s path, exploring a wide array of questions that required expertise in the vacuum ultraviolet. Tousey designed a vacuum spectrograph to study the optical characteristics of fluorite, a crystal that remains transparent deep into the ultraviolet and so can be useful for vacuum ultraviolet instrumentation. Throughout his graduate years, though his family continued to be prosperous, Tousey was largely supported by a series of substantial Harvard physics fellowships: the Whiting (1929–1931), the Tyndall (1931–1932), and the Bayard Cutting, which he won two years in a row, supported by Lyman. His 1936 thesis put him into contact with the machinist David Mann, head of the Physics Department shop, with whom he had a long fruitful collaboration. Tousey became especially adept at making his vacuum systems efficient and reliable, searching for leaks and handling humidity problems, though he recalls a certain amount of impatience working through the elaborate procedures Lyman had developed.

Tousey married Ruth Lowe in 1932. They met as undergraduates at Tufts, and shared interests in classical music, especially chamber ensembles, which they often entertained at their home.

After graduation Tousey stayed on in Lyman’s laboratory as a tutor and laboratory researcher/instructor. He further developed his thesis for publication, mainly searching for refinements to methods in photographic photometry of the extreme ultraviolet centering on improving emulsion sensitivity using different fluorescing oils. His goal was to overcome the failure of photographic reciprocity and thereby improve the medium as an objective sensor of radiation.

Advised by Saunders that a tenured position at Harvard was unlikely, Tousey gained an appointment to a faculty position in the Tufts physics department in 1936, something that required, as he recalled in an interview, intervention by his father, who was friendly with John Cousens, president of Tufts. Cousens endowed a temporary research instructorship for Tousey, which put him somewhat at odds with other members of the physics department. Tousey participated in all the physics offerings, but research remained his top priority.

In 1941 Tousey was given a leave of absence from Tufts for war-related work at the NRL. He had known Edward O. Hulburt, research director at NRL, from summers boating at Bucks Harbor, Maine, where his grandfather owned extensive holdings. Hulburt had visited Tousey at Harvard, and this led Tousey to write, asking if ajob was available. From this he received an excellent offer of employment, at a substantial raise.

Tousey moved his wife and daughter to Washington, D.C., in June 1941, anxious to get into war work. He found Hulburt’s Optics Division a small, friendly, and collegial group, in contrast to Tousey’s experience at Tufts, and during the war years Tousey contributed to many distinct problem areas the laboratory was concerned with, ranging from vision problems with binoculars and telescopes, to problems of night vision, creating optical camouflage, and developing means of infrared surveillance. The Bureau of Aeronautics had asked the NRL to explore the use of stars for daytime navigation from aircraft and Tousey took the lead in this area, acquainting himself with physiological optics and problems of visibility through haze and fog as well as techniques to assess sky brightness in the optical range. Tousey designed and built a periscopic telescope for aircraft that employed a prism to look at different parts of the sky. Advised by the Harvard astronomer Donald Menzel, Tousey carried his equipment to the High Altitude Observatory in Climax, Colorado, and through this came to know Walter Orr Roberts and other astronomers who were investigating relationships between solar activity and ionospheric characteristics. Tousey also carried his equipment on many aircraft, but out of this came an increased interest in the visibility of point sources in fields of extended brightness, which led to his participation in the Army-Navy Office of Scientific Research and Development (OSRD) Committee on Vision. Tousey also applied his knowledge of physiological optics to a study of the nighttime visibility of objects and limitations caused by dark adaptation and night myopia. He also explored infrared visibility searching for secure methods of communication. And he continued earlier research on ultraviolet reflectance.

In late 1945, Hulburt casually asked Tousey if he might be interested in securing the spectrum of the Sun from a V-2 rocket. Hulburt had just attended a preliminary meeting of other NRL scientists with officers from the U.S. Army Ordnance department that was charged with testing and evaluating captured German V-2 missiles at White Sands, New Mexico. Army Ordnance invited both military and civilian groups to build a wide variety of instruments for flights on these missiles, for basic research related to improving guided missile technologies and a general understanding of the medium through which missiles traveled.

Tousey, intrigued, knew from the start that no laboratory spectrograph could possibly survive a rocket flight, and believed as well that photographic recording was the only way to gain reliable spectroscopic evidence in that day. Physical retrieval became a primary technical hurdle, as did devising a means of acquiring sunlight from a spinning and tumbling rocket. Starting in February 1946 he led a small group of engineers, physicists, and technicians to design a new and unique form of ultraviolet spectrograph. He replaced the classical entrance slit with a pair of tiny lithium fluoride beads barely a few millimeters in diameter. These beads could capture sunlight like ultrawide-angled lenses and the streaks formed by the moving solar image (caused by the tossing rocket) simulated the entrance slit of a proper spectrograph. Light from either bead was folded by mirrors and sent to a single Rowland grating that both focused and dispersed the sunlight onto specially sensitized 35-millimeter roll film. The film itself was carefully prepared to avoid static electrical damage from rolling over metal surfaces in a vacuum, and once exposed in a series of frames taken during flight, was wound into a thick-walled cassette of armor-piercing steel to improve the chances of physical recovery. The spectrograph was designed to fit into the conical nose cone, or warhead, of the missile. Because the army was already firing these missiles, lead time was very short, so Tousey contracted with Baird Associates of Cambridge, Massachusetts, to build six units. The first was flown in June and was never recovered, even after weeks of digging. German advisors suggested putting the spectrograph in a tail fin, and adding explosive charges to break apart the missile upon reentry. The tail section would then crash at subsonic speeds and increase the chance of recovery. A second flight on 10 October 1946 was completely successful. This was the twelfth American launch of a V-2. It rose to 173 kilometers in 227 seconds, and was successfully blown apart before landing. It took almost four days to find the spectrograph in the desert sands and retrieve the film cassette for processing back in Washington. Finally, between 18 and 21 October the film was processed and showed solar spectra to as far as 2,100 angstroms, far beyond the ultraviolet cutoff of Earth’s atmosphere (at 2,900 angstroms). Moreover, the series of spectra obtained at different altitudes during the flight penetrated to different ultraviolet levels, which was interpreted as a record of passage through Earth’s absorbing ozone layer. On 30 October 1946, the Washington Post hailed the detection on page 1.

Subsequent V-2 flights carried the remainder of the Baird instruments, while Tousey and his team planned modifications to improve the fidelity of the spectra. A second round of Baird instruments was also contracted, and flown through 1948. The first spectra were indeed very crude, and far below the quality hoped for by astrophysicists interested in composition studies of the solar atmosphere. They were fine for Tousey’s and the NRL’s purposes, mainly to demonstrate feasibility, point the way for technical improvements, and to explore the structure of Earth’s ozone layer. But they did not penetrate as deeply as Tousey and his navy patrons hoped for: the goal was to reach the realm where solar radiation was believed to alter Earth’s ionosphere, and hence to influence long-range communications capabilities. Reaching this region, it was hoped, would reveal the actual spectral mechanisms influencing the ionosphere, which would lead to predictive mechanisms of obvious tactical interest.

By 1949, Tousey’s team was preparing far more efficient spectroscopic instruments for flights on new American-made vehicles, such as the navy’s Viking and Aerobee sounding rockets. They continued to study near-ultraviolet ozone structure in detail, obtaining data that were widely regarded as definitive. But to reach the extreme ultraviolet region surrounding the Lyman alpha line (the first resonant line of hydrogen at 1,216 angstroms, named for Tousey’s Harvard mentor) they sought out new means of detection and also promoted ways to increase exposure times during the short flight of a sounding rocket. Although still wedded to photographic technologies, Tousey teamed up with Kenichi Watanabe to explore using manganese-activated calcium sulfate phosphors and filters to reach the ultraviolet. At about the same time, a parallel NRL group effort headed by Herbert Friedman employed combinations of electronic halogen counters and filters. Both groups detected the Lyman alpha region but failed to explore its structure in detail. Tousey was convinced that only photography could do the job, and so parts of his team tried to develop gim-balled servo-feedback systems that acted as homing devices, allowing the spectrograph to lock onto the Sun throughout the flight. Efforts to achieve this new level of sophistication at both the NRL and the Applied Physics Laboratory failed time and again in the late 1940s and early 1950s. Finally, a group headed by William Rense at the University of Colorado was successful, with a lightweight biaxial pointing control carrying a grazing-incidence spectrograph developed for a series of air force Aerobee rockets. They first photographed the Lyman alpha line in December 1952, largely confirming the estimates made by the NRL groups.

Throughout the 1950s, Tousey’s group continued to refine their techniques, pushing on several fronts. They worked to achieve both better spectral resolution and better ultraviolet penetration. The small Aerobees were the only launch vehicle available for sounding rocket flights, but they were adequate to carry clusters of stabilized instruments weighing in the range of 10 kilograms or so to well over 100 kilometers altitude, within budgets accessible to institutions such as the NRL. As a result, Tousey enjoyed little competition during this period beyond other groups at the NRL, and at the Air Force Cambridge Research Center based at Hanscomb Field, Massachusetts, where Watanabe had moved to develop systems based upon photoelectric and electronic technologies. Pointing controls were procured from the University of Colorado group, which had left academe to form a subsidiary to Ball Brothers Corporation in Boulder, Colorado. The NRL spectrographs now had proper slits, higher dispersion through echelle and doubly dispersing systems, greater resolution, and more sophisticated ways of eliminating stray visible light.

As a result, they were able to explore the fine structure in the region surrounding Lyman alpha, as well as record thousands of spectral features throughout the ultraviolet, both in absorption, and blueward of 2,000 angstroms, in emission, all the way down to 977 angstroms. They were also the first to create an ultraviolet spectroheliogram, an image of the full solar disk in the light of hydrogen at Lyman alpha. As they increased the sensitivity of their instruments, Tousey’s group also started to make observations at night, mainly to assess ultraviolet airglow and other geocoronal phenomena.

One of the hallmarks of Tousey’s career was persistence. As he noted in a 1967 review article, he continued to work to refine the ultraviolet solar line spectrum ever since obtaining the first one in 1946. An improved echelle design they adopted in 1952 did not work to their satisfaction until an Aerobee flight in 1961. Even so, the frustrations and challenges they faced, working within the NRL infrastructure, were nothing compared to those in the post-Sputnik National Aeronautics and Space Administration (NASA) era when both the pace and the possibilities for expanded activities grew immensely.

The NASA Era. Tousey was never particularly interested in leaving the NRL for NASA, as many of his group did. Rather he continued to concentrate on the local level, on

instrument development, rather than institutional development on a national scale. His expertise was, of course, highly valued, especially by his former colleagues who were now NASA employees, and so his access to satellite berths was relatively unproblematic. This was certainly true for the various instrumented programs NASA developed, such as the Explorer series and the Orbiting Solar Observatory (OSO) series, but it became very complex and frustrating in the programs where human spaceflight was the primary motivation.

During the 1960s, his team continued to fly instrumentation on Aerobees, and he was willing to provide instrumentation for human flights during the Gemini and Apollo programs, although he found this effort particularly frustrating, overcoming safety restrictions only to find that his airlock-based experiments were summarily canceled in favor of maximum egress access for the astronauts. Tousey had far more success in the OSO program, contributing extreme ultraviolet instrumentation for several flights in the 1960s and 1970s, as well as making one of the first attempts to fly a solar coronagraph, which had long been a dream not only of astronomers, but also of the air force and navy. The NRL white-light coronagraph, flown in 1965 on the second OSO, operated from February to November 1965. It used an external occulting disk to block out the bright solar image, rendering the faint outer atmosphere visible for some 1,000 orbits of the spacecraft and allowing for the first time a detailed record of structural changes in the outer atmosphere and their relation to other solar phenomena. His second flight of a coronagraph, on OSO 7, produced high-quality data for several years in the early 1970s.

Probably his largest involvement came with the human Skylab program starting in the late 1960s and lasting through the mid-1970s. He had been one of the primary experimenters on a canceled unmanned Advanced Orbiting Solar Observatory, and so was given first choices when those instruments were considered for a new post-Apollo program using surplus Apollo hardware. Among the eight major solar instruments on what was called the Apollo Telescope Mount for Skylab, Tousey was involved with at least four of them. He directed NRL teams to develop devices to maximize the use of long exposure times on the Skylab space station to gather extreme ultraviolet and soft x-ray spectral information that for the first time equaled ground-based visible studies in detail and resolution. His instruments worked in a broad wavelength range from the soft x-ray through the ultraviolet, employing a wide range of spectrograph and disperser designs, but typically using photographic recording, made possible because the film could be returned by the three crews working on the station. He also led the development of an instrument for recording television images of the Sun using an SEC Vidicon to allow onboard monitoring by the Skylab crews to focus in on interesting rapidly developing solar features. He was also involved in an extreme-ultraviolet double-dispersion photographic spectrograph, applying his experience with predisperser grating optics and using a photoelectric servo system to stabilize the solar image to better than to 1 second of arc at the limb. This instrument recorded 6,400 exposures. Tousey was also central in the NRL’s extreme ultraviolet spectrohelio-graph, which employed a slitless Wadsworth grating spectrograph with photographic recording to record high-dispersion images of the solar chromosphere at 2 seconds of arc spatial resolution.

Tousey remained active into the early part of the shuttle era, planning instruments for flight. Although he was enormously inventive and productive, he and his team were sometimes criticized for concentrating so much on the production of data, and less on its analysis and interpretation. Tousey openly recognized this as a matter of personal choice throughout his career. In 1967, in his Henry Norris Russell Prize Lecture before the American Astronomical Society, he observed that “Interpretation of the results [by astronomers] does seem to the experimenters to have lagged, but I know, too, that the experimenters themselves have been slow in publishing completed results” (Tousey, 1967b, p. 251).

Tousey was elected a member of the National Academy of Sciences in 1960, and following that received many awards and honors from the academy, the Optical Society of America, the navy, the Royal Astronomical Society, and NASA. He retired in 1978, remaining active as a consultant. He died of pneumonia on 15 April 1997, at the age of eighty-eight.

BIBLIOGRAPHY

Tousey’s professional papers between the 1940s and 1980s, but chiefly from the 1960s, are preserved in the National Air and Space Museum archives and include correspondence, speeches, minutes, and proceedings, photographs, prints, film, oral history transcripts, lantern slides, and glass plates.

WORKS BY TOUSEY

“An Apparatus for the Measurement of Reflecting Powers with Application to Fluorite at 1216 A.” Unpublished PhD diss., Harvard University, 1936.

“Optical Constants of Fluorite in the Extreme Ultraviolet.” Physical Review 50, no. 11 (1936): 1057–1066.

With William A. Baum, F. S. Johnson, J. J. Oberly, et al. “Solar Ultraviolet Spectrum to 88 Kilometers.” Physical Review 70 (1946): 781–782.

With F. S. Johnson and J. D. Purcell. “Measurements of the Vertical Distribution of Atmospheric Ozone from Rockets.” Journal of Geophysical Research 56 (1951): 583–594.

“Solar Spectroscopy in the Far Ultraviolet.” Journal of the Optical Society of America 51 (1961): 384–395.

“The Spectrum of the Sun in the Extreme Ultraviolet.” Quarterly Journal of the Royal Astronomical Society 5 (1964): 123–144.

“Highlights of Twenty Years of Optical Space Research.” Applied Optics 6 (1967a): 2044–2070.

“Some Results of Twenty Years of Extreme Ultraviolet Solar Research.” Astrophysical Journal 149 (1967b): 239–252. The AAS Henry Norris Russell Lecture.

With J.-D. F. Bartoe, J. D. Bohlin, G. E. Brueckner, et al. “A Preliminary Study of the Extreme Ultraviolet Spectroheliograms from Skylab.” Solar Physics 33 (1973): 265–280.

With M. J. Koomen, C. R. Detwiler, G. E. Brueckner, et al. “White Light Coronagraph in OSO-7.” Applied Optics 14 (1975): 743–751.

“Interview with Dr. Richard Tousey” by David Compton. 20 April 1976. NASA History Office. Available from http://history.nasa.gov/oralhistory/hqinventory.doc.

“Apollo Telescope Mount on Skylab: An Overview.” Applied Optics 16 (1977): 825–836.

“Richard Tousey Oral History” interview by David DeVorkin. 17 November 1981, and 8 January and 4 June 1982. Space Astronomy Oral History Project, National Air and Space Museum Archives.

“Solar Spectroscopy from Rowland to SOT.” Vistas in Astronomy 29 (1986): 175–199.

With G. D. Sandlin, J.-D. F. Bartoe, G. E. Brueckner, et al. “The High-Resolution Solar Spectrum, 1175–1710 Å.” Astrophysical Journal Supplement 61 (August 1986): 801–898.

OTHER SOURCES

Baum, William A. “Richard Tousey.” Biographical Memoirs, vol. 81. Washington, DC: National Academy of Sciences, 2002.

Compton, W. David, and Charles D. Benson. Living and Working in Space: A History of Skylab. Washington, DC: National Aeronautics and Space Administration, 1983.

DeVorkin, David H. “Richard Tousey and His Beady-Eyed V-2s.” Air & Space Smithsonian 1 (June/July 1986): 86–94.

———. Science with a Vengeance: How the Military Created the US Space Sciences after World War II. New York: Springer-Verlag, 1992. Reprinted 1993, paperback study edition.

Friedman, Herbert, Nicholas J. Koomen, W. R. Hunter, et al. “Richard Tousey 1908–1997: In Memoriam.” Optics & Photonics News 8 (July 1997): 9.

David H. DeVorkin