Spitzer Lyman Jr

views updated

SPITZER LYMAN JR

(b. Toledo, Ohio, 26 June 1914; d. Princeton, New Jersey, 31 March 1997), theoretical astrophysics, physics of the interstellar medium, stellar dynamics, space astronomy, plasma physics, and controlled fusion.

Spitzer was one of the leaders of mid- to late-twentieth-century American theoretical astrophysics, specializing in the physics of the interstellar medium, broadly based studies in stellar dynamics, large-scale applied studies in plasma physics and ultraviolet space astronomy. He will be remembered by generations of astronomers as a gifted teacher, chairman of Princeton’s Department of Astrophysical Sciences and director of the Princeton Observatory, and by the science-aware public as the inspirational force advocating what became the Hubble Space Telescope.

Early Life and Training Born 26 June 1914 into a seventh-generation American family, Spitzer was one of four children (two older sisters and a younger brother) of a prosperous manufacturer of paper boxes and paper products in Toledo, Ohio, who had previously been in the municipal bond trade. His father, Lyman Spitzer, had trained at Phillips Academy Andover and Yale, and his mother, Blanche Brumback, at Vassar, and the family was actively interested in fine arts and intellectual pursuits. The family attended the First Congregational Church in Toledo, where the father was an active board member. Spitzer remembered his father encouraging him to pursue a college career as a professor.

Spitzer attended public schools in Toledo and then followed in his father’s footsteps to Andover, where he came under the guidance of the physics professor Frederick M. Boyce. Spitzer and a classmate, Max Millikan, convinced Boyce to add a course in astronomy after they had read popular texts by Arthur Stanley Eddington and James Jeans. Spitzer was especially attracted to physical problems because at Andover he found, much to his satisfaction, that he had “an ability to visualize what goes on physically in terms of physical models … I can see how things fit together, and sort of understand the physical process.” (“Oral History Interview with Lyman Spitzer Jr.” [hereinafter OHI], p. 8; all quotes are from the 1977 interview). While Spitzer was at Andover, Boyce took his class on a field trip to Boston to hear the astronomer Henry Norris Russell talk about stellar evolution. Also during his Andover years, the family took extended trips to Europe, spending six months in Rome and four months in Paris as well as extended trips to California, England, and Switzerland, where he gained a lifelong passion for mountain climbing.

Yale was Spitzer’s choice for college after considering alternatives to the family tradition. He was supported by his family, but also by prizes won at Andover that covered tuition at Yale. He chose Yale for its social atmosphere and concentrated in physics, where he came under the supervision of Alan T. Waterman and under the influence of Leigh Page. Spitzer excelled, managing to be excused from formal course requirements in favor of independent study. In his junior year he reunited with Max Millikan as a roommate. The two had kept in touch after Max attended his famous father’s school, the California Institute of Technology (Caltech); Spitzer traveled to California, visited Max in Pasadena, and they climbed the San Gabriel range. During these trips, stimulated by the serials he was reading in Amazing Stories and Hugo Gernsbach’s Astounding Science Fiction, Spitzer mused on ways to create regional and even global subterranean transportation systems using diversification and branching concepts found in telephone network models, where small cars suspended in frictionless electromagnetic fields were subject only to gravity.

Under Waterman, Spitzer took a passing interest in schemes for particle accelerators, but managed only rudimentary experiments concentrating more on theoretical analysis and modeling. He was active in campus life, becoming chairman of the Yale Daily News. He took part in various informal discussion circles and came to know Richard Bissell, Walt Rostow, Bill Hull, and Charles Seymour. These contacts stimulated an interest in theoretical economics for a while as he pondered how he might apply his passion for modeling to both physics and economic theory. Advised by his father that in economics it is “very difficult to establish the correctness of any viewpoint” (OHI, p. 16) Spitzer opted for physics, graduating in 1935.

After Yale, Spitzer spent a year at St. John’s College, Cambridge University, on a Lady Julia Henry Fellowship to study nuclear physics. He was assigned to Ralph Fowler, who disregarded his interests and directed him to read a recent Bengt Strömgren paper on electron capture and Fraunhofer line intensities, which Spitzer enjoyed. At a subsequent tutorial session, however, Fowler announced he was taking a leave of absence to be at Princeton, and suggested he read under Eddington on noncoherent scattering theory. Spitzer did so, meeting Eddington less than five times during the year, once again finding satisfaction in his ability to physically visualize the scattering processes he was modeling. During his Cambridge year Spitzer came to know Fred Hoyle and Max Krook, and often attended evening seminars and discussions of modern topics led by Subramanyan Chandrasekhar (known informally to colleagues as Chandra), who was then a Trinity Fellow. Spitzer greatly enjoyed Chandra’s lectures in stellar structure, “a wonderful aesthetic experience” (OHI, p. 20). During his year at Cambridge, Spitzer decided to enroll at Princeton, entering the graduate school intending to combine theoretical physics with astronomy under Russell.

Spitzer’s plan was to enroll in courses taught by Eugene Wigner, Edward Uhler Condon, and Howard Percy Robertson among other strong theorists at Princeton; take the general examinations in theoretical physics; and then perhaps do a thesis informed by Russell’s interests. Russell knew some excellent spectroscopic plates were available at Mount Wilson Observatory and suggested Spitzer visit Pasadena in the summer of 1937 and use them to analyze the spectra of M supergiant stars.

During his graduate years at Princeton, Spitzer attended Albert Einstein’s occasional lectures, but spent more and more time with Russell, informally at first in the astronomy library, and eventually in more structured sessions as Russell revised his famous textbook and engaged students and postdoctoral fellows in discussions that would inform the revisions. These discussions, which included the visiting Cambridge theorist Ray Lyttleton, mainly dealt with Russell’s passion at the time: the origin of the solar system. This led Spitzer to explore what would happen if the Sun were to encounter another star and suffer a tidal collision. Would material drawn off the two stars condense into planetary bodies or dissipate? This was a major question in that day before nebular condensation theories were successfully placed on a physically plausible basis. Spitzer had been interested in stellar atmosphere theory at Cambridge, and believed he could apply it to answer this question, which held the key to accepting or rejecting the idea that the solar system arose from a chance collision of the Sun with a passing star. Eventually, during his postdoctoral year at Harvard, Spitzer would show conclusively that the tidal filaments would not coalesce, but would dissipate. His work proved to be a watershed study in the history of that subject.

Postdoctoral Years and War Work After a summer in Switzerland with his family, Spitzer, supported by a National Research Council postdoctoral fellowship, moved to Harvard, where he completed and published his study of filament dissipation. At the time, the question had become a contentious topic of debate between Lyttleton and Willem J. Luyten, and Spitzer distinguished himself by soberly and diplomatically offering conclusive evidence of his findings, avoiding the ad hominem debate, and settling the matter. Spitzer found Harvard very stimulating; his office mate was Leo Goldberg and he came in contact with Theodore Sterne, Lawrence Aller, Donald Menzel, Fred Whipple, and Cecilia Payne-Gaposchkin. He was most impressed with Martin Schwarzschild’s colloquia and his always-prescient questions and commentary. Harvard astronomy was distinguished by social interaction, personified by Shapley’s “Hollow Squares.” Bart Bok followed Shapley’s style, offering “social seminars” that graduate students and postdocs attended. Spitzer recalls some of his most fruitful ideas flowing from these occasions, such as his interest in the dynamics of globular clusters as isothermal gas spheres.

During his postdoctoral year, Spitzer was invited to join the Harvard Society of Fellows but chose instead to accept an offer from the Yale physics department in the fall of 1939 as an instructor. Spitzer engaged in undergraduate physics teaching and studied the dynamics of galaxies and what circumstances favored spirals and ellipticals, finding important influences from the presence or absence of rotation and of the existence of an interstellar medium of gas and dust. He maintained this interest while at Yale, where he had a little contact with Yale astronomers, mainly Frank Schlesinger, but remained wholly in physics. As the war intensified in Europe in early 1941, Spitzer volunteered to give a graduate course in aerodynamic theory as a means to acquaint himself with physics useful for wartime research.

In June 1940 he and Doreen Canaday were married. Both from Toledo, they had known each other for some time, enjoyed dancing together, and saw each other in the summers during and after graduate school. She had been active in archaeology but did not continue this interest professionally after marriage. Eventually they had four children: a son, Nicholas, and three daughters, Dionis, Sarah, and Lydia.

Spitzer left Yale in January 1942 for war work in an National Defense Research Committee (NDRC) Division 6 contract office connected with Columbia University devoted to undersea warfare. He had aligned with the “America First Committee” created within the Yale Law School, resisting involvement in the war, but after Pearl Harbor, all that vanished. The invitation was by telephone and Spitzer was asked to assist in the scientific administration and evaluation of underwater sound research, acting as liaison with navy personnel such as Roger Revelle. Offices were set up in the Empire State Building and in the later years of the war, Spitzer moved to Washington, DC, to head up a Sonar Analysis Group. His primary responsibility was to manage research, perform evaluative studies of underwater sound propagation, and eventually act as general editor of a major report, The Physics of Sound in the Sea. His wartime activities, especially with Revelle, sensitized him to new ways to conduct large-scale research and its management, including the creation of synergistic arrangements between universities and the military services.

Yale and Princeton Spitzer briefly considered an offer from the University of Pittsburgh to head the astronomy department, but at the end of the war returned to Yale, where President Seymour had promised he could set up an interdisciplinary “astrophysical unit” with a foot in both astronomy and physics. He was given an additional faculty slot to fill, and first asked Schwarzschild, then at Columbia, to join him. When Schwarzschild deferred, thinking the “unit” was an administrative oddity, he asked Rupert Wildt, who took the position.

Postwar Yale astronomy was experiencing small changes. Longtime director Schlesinger died in 1944, and was replaced by the mathematical astronomer Dirk Brouwer, who maintained Yale’s traditions in astrometry and celestial mechanics. Spitzer did what he could to establish new astrophysical programs, including a small consulting unit funded by the navy to analyze the data that were expected to flow from V-2 rocket flights of ultraviolet solar spectrographs. In mid-1946 he secured the funds and made plans, trying to attract Leo Goldberg to Yale. But the early data returns were woefully inadequate, promising no great improvements soon. Even so he consulted for Project RAND, producing a seminal and initially classified study on “Astronomical Advantages of an Extra-Terrestrial Observatory,” which outlined the astronomy that could be done with telescopes of various apertures in earth orbit, and notably offered his vision of how new technologies such as space telescopes would reveal new and unanticipated questions that would lead to new areas of exploration and knowledge. Although the physics department was indifferent to these activities, Brouwer chafed somewhat, especially at the creation of the consultant group.

Spitzer’s rekindled research activities now centered more and more on the physics of the interstellar medium although he was still contributing to stellar atmosphere theory, including a study of noncoherent scattering mechanisms in stellar atmospheres. Extending a set of three studies that were published in 1941 on the “Dynamics of the Interstellar Medium,” after the war Spitzer examined the temperature of the interstellar medium, the galactic magnetic field, and the formation and evolution of interstellar clouds.

His return to Yale, however, was brief. He had quietly always hoped to return to Princeton to replace Russell, and the opportunity came in 1947. The process from Princeton’s side, however, was protracted and far from straightforward, and included offers to Svein Rosseland and Chandrasekhar. The goal had been to replace Russell with someone equally prominent. But the problem was that Russell had so neglected the astronomical infrastructure of the observatory, there was not much to offer in his wake. Finally Princeton, realizing this, turned to Spitzer and offered him virtually a blank slate. When Spitzer responded with a very well received plan of action that included federal funding schemes, hiring Schwarzschild and maintaining formal connections to west coast observatories for periodic observing visits, Princeton happily accepted.

Spitzer and Schwarzschild together were a formidable team, one of the great astronomical teams of the second half of the twentieth century. Both were theorists, but with strong interests in observational work, and both labored to create a strong graduate program in modern astrophysics. Both believed in broadly based collaborative and inclusive styles of research, and both sought out expertise and interests in mainstream physical science, and Spitzer wholly supported Schwarzschild’s attention to computational mathematics and high-speed computing. Spitzer continued to pursue a coherent set of studies exploring the temperature and abundances of the elements in the interstellar medium, including studies of physical mechanisms in the interstellar medium that could produce the recently observed polarization in starlight. In a 1950 collaboration with Walter Baade, Spitzer suggested that the absence of interstellar material in some galaxies was caused by prior collisions between galaxies.

Plasma Physics at Princeton Spitzer’s interests in the physics of the interstellar medium directed his attention to problems in plasma physics and magnetohydrodynamics, partly aided by a visit of Hannes Alfvèn to Princeton. A few months prior, returning to Princeton from Pasadena, Spitzer had stopped in Los Alamos to confer with John Wheeler about matters relating to the development of the H-Bomb. Stanislaw Ulam and Edward Teller had just announced that they had a solution to the problem of energy losses through rapid cooling using radiation coupling for fuel compression, and Spitzer was intrigued by it. The two agreed to continue fusion research somehow at Princeton. Then, in the spring of 1951, after a spectacular but bogus announcement that Argentine scientists had succeeded in creating controlled nuclear fusion, Spitzer once again consulted Wheeler, who would have the last word on the matter. Together, they decided to develop a multifaceted government-funded program at Princeton to explore practical methods of controlled fusion as well as continue theoretical research on bomb development. Spitzer led the former effort, called “Matterhorn-S,” developing a magnetically confined plasma device, a “Stellerator” that would fuse hydrogen into helium in a slow controlled process, creating energy to drive electricity generators. Wheeler would manage “Matterhorn-B” to perform calculations predicting the characteristics of thermonuclear reactions. “Matterhorn,” coined by Spitzer in the spirit of climbing a great mountain, achieved notoriety when it faithfully predicted the characteristics for the thermonuclear stage of the first H-Bomb tests in November 1952. In fact, the test worked better than predicted, but very much along the theoretical lines established at Princeton. This achievement, classified of course, led to optimism for controlled fusion, and so Spitzer’s group grew rapidly. After a year of theoretical studies, he created a small experimental group, headed for a while by James Van Allen, and this grew exponentially, especially after it was declassified in 1958 as a result of the Geneva “Atoms for Peace” Conference. In 1958 it was renamed the Princeton Plasma Physics Laboratory. Early hopes for success, from evidence of neutron emission, soon were dashed because the emission came from instabilities in the plasma caused by turbulence. The problem of overcoming turbulence became the driving force beyond achieving the extreme temperatures needed for fusion. Spitzer remained director of the project until 1961, and left it only in 1966.

Space Astronomy Spitzer’s 1946 study for Project RAND was not stillborn in him, even though it remained classified for some time He promoted his ideas to colleagues but in the early years knew there was too much frustration associated with such efforts to attract a wide interest base. Yet he contributed to related studies, such as a 1947 report on the nature of the Earth’s atmosphere at 300 kilometers (186 miles), a 1950 report on satellite perturbations, and in 1952, for the Journal of the American Rocket Society, on interplanetary travel. This led to a televised speech in Princeton in 1954 that was translated by the French popular journal Ciel et Terre in 1955. He contributed a paper “On the Determination of Air Density from a Satellite” to a symposium organized by Van Allen on the Scientific Uses of Earth Satellites in 1956, and in the wake of Sputnik described observations of the interstellar medium that could be made from a satellite, as well as options for optical space telescopes. Starting in the mid- to late 1950s, he avidly supported and facilitated Schwarzschild’s program of building and flying a series of balloon-borne telescopes to study the Sun and then nonsolar objects, “Project Stratoscope.” Always taking the long view, he regarded this as a step in the direction of a true space telescope capability.

Spitzer will be remembered for his advocacy of a large orbiting optical telescope, and his name is central to the history of the Hubble Space Telescope. By the time he resigned from Matterhorn, his planned payload for an Orbiting Astronomical Observatory (OAO) mission was well underway, having started after Spitzer’s initial response to queries ranging from the Air Force to Lloyd Berkner of the National Academy in 1958 asking what astronomers would do if they had access to space. Spitzer was one of several who immediately proposed some form of space telescope, and this led to the National Aeronautics and Space Administration (NASA) OAO series, which by the early 1960s included a 81-centimeter (32-inch) reflecting telescope for high-resolution nonsolar ultraviolet spectroscopic studies. This eventually came to be called the “Princeton Experiment Package” aboard OAO-III, Copernicus, launched in 1972. By then, Princeton under Spitzer had been vigorously exploring space astronomy, including Schwarzschild’s “Project Stratoscope” and a sounding rocket program, and Spitzer himself was a leading voice articulating what a true optical space telescope might look like, first at a summer study in Iowa in 1962, and then more formally in 1965 after a study at Wood’s Hole that called for a 305-centimeter (120-inch) optical reflector. Spitzer chaired an ad hoc committee arising from the proposal.

Even though Spitzer and Princeton remained central to the definition of the telescope, and Spitzer was no doubt among its most passionate and effective advocates in both astronomy and in Washington, their successive proposals, first to build a wide-field camera and then to host the scientific headquarters for the facility, were not successful. What would become the Wide Field–Planetary Camera was decided on the basis of the promise of new technologies (charge-coupled devices [CCDs] over traditional Secondary Electron Conduction [SEC] Vidicons proposed by Princeton) and the Space Telescope Science Institute’s more favorable and effective administrative and political circumstances offered by a coherent proposal from the Association of Universities for Research in Astronomy (AURA) consortia that selected Johns Hopkins University as the site. These were both disappointments, of course, both to the institution and for Spitzer, but both managed to maintain positive leading roles in the Hubble mission and space astronomy generally.

Spitzer was an active member of policymaking and oversight groups in astronomy, including the National Academy of Sciences Decadal survey led by Jesse Green-stein in the 1970s. He held membership on the Astronomy Missions Board, the editorial board of the Astrophysical Journal, and many other posts of similar importance. He was one of the first (1953) incumbents of the Henry Norris Russell Lectureship of the American Astronomical Society (AAS), and starting in the 1970s received virtually every major prize given to astronomers, as well as the National Medal of Science in 1979 and the Crafoord Prize in 1985. He was president of the AAS from 1960 to 1962. He has an asteroid named in his honor as well as a major NASA infrared satellite, and to recognize his support for mountain climbing, the American Alpine Club created the Lyman Spitzer Climbing Grants Program, known also as the Lyman Spitzer Cutting Edge Award.

Spitzer maintained active research and publishing until his death, contributing to understanding the physics of the interstellar medium. His latest papers remained in the early 2000s highly cited works, and his collaboration with Ed Fitzpatrick as a guaranteed time observer on the Hubble Space Telescope resulted in the recognition of the existence of a new class of objects called “proplyds”—protoplanetary disks encapsulating stars still forming in dense interstellar clouds. Spitzer died suddenly at home after a normal working day. Appreciations by his colleagues attest to his great humanity.

BIBLIOGRAPHY

Archives held at Princeton University include a collection of Spitzer’s papers (1936–1997) and Records of the Department of Astrophysical Sciences (1835–1988), both available at the Princeton University Department of Special Collections, Princeton, New Jersey. Project Matterhorn publications and reports (1951–1958) are available at the Furth Plasma Physics Laboratory, Forrestal Campus of Princeton University, Princeton, New Jersey. A number of interviews with Spitzer are available at the American Institute of Physics, Center for History of Physics, Niels Bohr Library, College Park, Maryland, and as part of the Space Astronomy Oral History Project of the National Air and Space Museum Archives, Smithsonian Institution, Washington, DC.

WORKS BY SPITZER

“The Stability of Isolated Clusters.” Monthly Notices of the Royal Astronomical Society 100 (1940): 396–413.

“The Dynamics of the Interstellar Medium. III. Galactic Distribution.” Astrophysical Journal 95 (1942): 329–344.

“The Temperature of Interstellar Matter. I.” Astrophysical Journal 107 (1948): 6–33.

With Walter Baade. “Stellar Populations and Collisions of Galaxies.” Astrophysical Journal 113 (1951): 413–418.

With David R. Bates. “The Density of Molecules in Interstellarn Space.” Astrophysical Journal 113 (1951): 441–463.

With Martin Schwarzschild. “The Possible Influence of Interstellar Clouds on Stellar Velocities.” Astrophysical Journal114 (1951): 385–397.

With Paul McRae Routly. “A Comparison of the Components in Interstellar Sodium and Calcium.” Astrophysical Journal 115 (1952): 227–243.

“On a Possible Interstellar Galactic Corona.” Astrophysical Journal 124 (1956): 20–34.

Physics of Fully Ionized Gases. New York: Interscience, 1956.

With Leon Mestel. “Star Formation in Magnetic Dust Clouds.” Monthly Notices of the Royal Astronomical Society 116 (1956): 503–514.

“Distribution of Galactic Clusters.” Astrophysical Journal 127 (1958): 17–27.

With William C. Saslaw. “On the Evolution of Galactic Nuclei.” Astrophysical Journal 143 (1966): 400–419.

“Astronomical Research with the Large Space Telescope.” Science 161, no. 3838 (1968): 225–229.

Diffuse Matter in Space. New York: Interscience, 1968.

With Michael H. Hart. “Random Gravitational Encounters and the Evolution of Spherical Systems. I. Method.” Astrophysical Journal 164 (1971): 399–409.

With Jeremiah P. Ostriker and Roger Chevalier. “On the Evolution of Globular Clusters.” Astrophysical Journal 176, part 2 (1972): L51–L56.

With J. B. Rogerson, J. F. Drake, et al. “Spectrophotometric Results from the Copernicus Satellite. I. Instrumentation and Performance.” Astrophysical Journal 181, part 2 (1973): L97–L102.

——. “Spectrophotometric Results from the Copernicus Satellite. IV. Molecular Hydrogen in Interstellar Space.” Astrophysical Journal 181, part 2 (1973): L116–L121.

——. “Spectrophotometric Results from the Copernicus Satellite. VI. Extinction by Grains at Wavelengths between 1200 and 1000 Å.”Astrophysical Journal 182 (1973): L1–L6.

With Edward B. Jenkins. “Ultraviolet Studies of the Interstellar Gas.” In Annual Review of Astronomy and Astrophysics13 (1975): 133–164.

With Scott D. Tremaine and Jeremiah P. Ostriker. “The Formation of the Nuclei of Galaxies. I - M31.” Astrophysical Journal 196, part 1 (1975): 407–411.

“Oral History Interview with Lyman Spitzer, Jr., 8 April 1977 and 10 May 1978.” Interview by David DeVorkin. College Park, Maryland: American Institute of Physics, Center for History of Physics, Niels Bohr Library, 1977–1978. All quotes are from the 1977 interview.

Physical Processes in the Interstellar Medium. New York: J. Wiley, 1978.

Searching between the Stars. New Haven, CT: Yale University Press, 1982.

With Ralph C. Bohlin, Edward B. Jenkins, Blair D. Savage, et al. “A Survey of Ultraviolet Interstellar Absorption Lines.” Astrophysical Journal Supplement Series 51 (1983): 277–308.

Dynamical Evolution of Globular Clusters. Princeton, NJ, Princeton University Press, 1987.

“Dreams, Stars, and Electrons.” Annual Review of Astronomy and Astrophysics27 (1989): 1–17.

With Edward Fitzpatrick. “Composition of Interstellar Clouds in the Disk and Halo. IV. HD 215733.” Astrophysical Journal475, part 1 (1997): 623–641.

With Jeremiah P. Ostriker, eds. Dreams, Stars, and Electrons: Selected Writings of Lyman Spitzer, Jr. Princeton, NJ: Princeton University Press, 1997. Includes detailed annotations by Spitzer of some thirty-two works he felt best describe his career accomplishments and interests.

———. “Hubble Space Telescope Observations of Orion Nebula, Helix Nebula, and NGC 6822.” Technical Report, Princeton University. NASA STI/Recon Technical Report N. (1999).

OTHER SOURCES

Bahcall, John N., and Jeremiah P. Ostriker. “Lyman Spitzer Jr.” Physics Today 50, no. 10 (1997): 123–124.

Bromberg, Joan Lisa. Fusion: Science, Politics, and the Invention of a New Energy Source. Cambridge, MA: MIT Press, 1982.

DeVorkin, David H. Henry Norris Russell: Dean of American Astronomers. Princeton, NJ: Princeton University Press, 2000.

Field, George B. “Lyman Spitzer, Jr. (1914–1997).” Publications of the Astronomical Society of the Pacific 110, no. 745 (1998): 215–222.

King, Ivan R. “Obituary: Lyman Spitzer, 1914-1997.” Bulletin of the American Astronomical Society 29, no. 4 (1997): 1489–1491.

Smith, Robert W., with contributions by Paul A. Hanle, Robert H. Kargon, and Joseph N. Tatarewicz. The Space Telescope: A Study of NASA, Science, Technology, and Politics. New York: Cambridge University Press, 1989.

David DeVorkin