Tinsley, Beatrice Muriel Hill
TINSLEY, BEATRICE MURIEL HILL
(b. Chester, United Kingdom, 27 January 1941;
d. New Haven, Connecticut, 23 March 1981), astronomy, cosmology, evolution of galaxies, education.
Tinsley was one of the first to show that galaxies evolve with time. She was famed as a synthesizer, constructing models that gave new ways of measuring the universe and creating new pathways for cosmologists. Her work, including collaboration with colleagues and her inspiring teaching, was honored by the American Astronomical Society with the Beatrice M. Tinsley Prize, first awarded in 1986. It recognizes “an outstanding research contribution to astronomy or astrophysics, of an exceptionally creative or innovative character.” The University of Texas in Austin endowed a chair in her name in 1985.
Origins. Beatrice Muriel Hill was born prematurely after an air raid in World War II, and was not expected to live. Her unusual zest for living was evident from early childhood, however. It was to be said of her that she did not waste a minute of her life, whether it be purposeful play, constructing and following fourteen-hour daily timetables during her school days, or teaching herself to use her left hand to work on scientific papers in the last few months of her life, when partially paralyzed by a brain tumor caused by cancer.
She was the middle of three daughters born to Edward and Jean Hill, née Morton. Her parents, both from prominent families, instilled in their children a knowledge of their forebears, and made it plain that great things were expected of them. Innovative chemists were featured in Jean Hill’s family company, Morton Sundour Fabrics. Edward Hill came from a line of land and shipping owners. The great influence in their lives, hence their children's, was the interfaith religious movement begun by an American, Frank Buchman, and known as the Oxford Group (not to be confused with Anglicanism’s Oxford Movement), later Moral Re-Armament. Adherents were to live by the “Four Absolutes”: Absolute Love, Absolute Purity, Absolute Honesty, and Absolute Unselfishness.
Beatrice grew up with religious and philosophical discussions around the dinner table, the big questions of life, death and the universe. While always respecting her parents and seeking their approval, she came to disagree with many of their beliefs and their strict interpretation of the Absolutes. She sought other answers, and turned to science.
From babyhood Beatrice had been cared for by a nanny, as were her parents before her. The austerity of postwar England, and the fact that Edward Hill had not been able to settle to a career, made him look to new horizons. In 1946 the family migrated to New Zealand. There Edward Hill was ordained in the Church of England, although he resigned from parish work to become mayor of the city of New Plymouth in 1953. Left behind was this nanny, the substitute-mother. Beatrice was to say that “a black hole of grief” opened up in her. The nanny was later brought out from England, but a second and final separation in 1949 desolated the child. It was soon after this that Beatrice drew up a timetable for living in which all her waking hours were purposefully occupied.
She increasingly became a “good” daughter, trying to please her parents while not following their religious beliefs. She also came to believe they needed protection from the barbs of criticism directed at them in their public lives: protecting them from what they did not need to know. Thus her long letters home, to the end of her life, give only a partial picture of what she was thinking and doing. Nevertheless, these letters, selected by her father with a narrative framework and published as My Daughter Beatrice, give an unusual insight into the development of a cosmologist.
Education. Beatrice’s childhood was filled with music, books, ponies, and exploration of nature. At high school she excelled in every subject although she was always by far the youngest in her class. She was expected to gain a university scholarship in languages, or possibly become a professional violinist. Instead she stood firm and persuaded her headmistress and parents that mathematics, physics, and chemistry were her subjects. Astronomy was her goal. Working largely by herself she won a top scholarship, and in 1958 enrolled in the sciences at the University of Canterbury in Christchurch.
The young Beatrice’s attempts to become part of a greater whole, as well as to shield her parents from anxiety if she had boyfriends, had led to her becoming engaged to be married when she was still only sixteen, an engagement soon painlessly broken. She did marry the next man to ask her, Brian Tinsley, a well-regarded science student four years her senior who was specializing in spectroscopy. At twenty the first of her classmates to marry, Beatrice by then was recognized as one of the university’s outstanding students. Other than by taking a similar scientific rather than narrowly religious view of life, the Tinsleys were not well matched, as Beatrice was later to write. For many years, however, she strove to be her ideal of a good wife, although she had to contort her own life in the process.
Her student life was enriched by playing the violin in an orchestra, belonging to a philosophical debating club, the Socratic Society, and doing volunteer community work. She also had the good fortune to be able to use what was only the second computer to be imported into New Zealand, thus becoming familiar with an essential tool early in her short career. Cosmology was the subject she wanted to pursue but it was not then taught at Canterbury University. Instead she was advised to write her MSc thesis on “Analysis of the optical absorption spectrum of neodymium magnesium nitrate.” She had to fit experimental data into a scheme of theoretical expression, a model to accommodate all the data published by other workers to that date. She graduated with top honors and won all available prizes.
To advance their careers, both Tinsleys needed to study abroad. Brian, working on his doctorate, accepted a research position at the Southwest Center for Advanced Studies, Dallas, Texas (which later became part of the University of Texas), where Beatrice was assured she could use her postgraduate scholarship. She discovered, however, that no relevant teaching was available, so studied astronomy on her own. As precious time was passing, she decided to begin the family they had planned. It was when she was told she could not conceive that Beatrice talked the University of Texas at Austin (UTA) into accepting her as a PhD student in 1964. This involved spending four days weekly in Austin, and commuting 400 miles.
She exceeded expectations, completing her preliminary work in four months instead of the usual two years, then gaining her PhD in only twenty-three months instead of the expected five years. Her achievement was the more remarkable because, while working on her thesis, she felt she should accede to her husband’s request that they adopt a baby soon to be born to a member of his family. This was part of her concept of being a good wife, although they had earlier agreed they would not adopt until they both had suitable university positions away from Dallas.
As the leading astronomer Sandra Faber would later argue, although she had been drawn to astronomy by cosmology, she rapidly decided that the pursuit of cosmology called for a much better understanding of the development of galaxies. The key point was that if old galaxies were systematically different from young ones, then cosmological measurements that assumed they were the same were sure to be misleading. In her thesis Tinsley explored how galaxies change over time in color and luminosity as the stars within them age. She did this by developing computer models that employed both observational data and theoretical information on the evolution of stars. Although the basic idea was not original to her, Tinsley’s analysis was much more detailed than anything that had been done before and she produced numerical simulations. Her paper based on her thesis, “Evolution of the Stars and Gas in Galaxies,” broke wholly new scientific ground. Bold and wide-ranging, it foreshadowed her own future research, as even a casual reading of her more than one hundred published papers shows. It was to be said of her that, “with a degree of realism never achieved before,” she tackled in masterly fashion the evolution of stellar
populations in galaxies, and modeled the complex interplay between star formation, stellar evolution and the recycling of the interstellar medium (Faber, 1981, pp. 110–111). Tinsley contended that the evolution of galaxies would produce much more significant changes in the brightness of galaxies than the small changes calculated to result from different cosmological models. She also suggested that different histories of star formation might explain the different sorts of normal galaxies without assuming different ages.
Selecting this paper for the Astrophysical Journal ’s 1999 centennial issue as one of the fifty-three seminal papers of the twentieth century, the AJ ’s editor, Robert Kennicutt Jr., has said its most enduring result is its clear demonstration that galaxy evolution is an eminently observable phenomenon. Within a decade this new subject was to grow into one of the largest subfields in extra-galactic astronomy. When the paper was first published in 1968, the very eminent astronomer Allan Sandage decried it. He contended that the universe was closed whereas Tinsley had argued that it was open. For some time Tins-ley felt her work was not fully appreciated. Astronomers such as Ivan King and Hyron Spinrad of the University of California at Berkeley, however, early showed an interest and recognition that came to her as “water in the desert,” Tinsley was to say. In turn, throughout her life she responded to and encouraged young astronomers, this being a much-appreciated component of her teaching style.
Family and Work. True to Beatrice’s belief that “the right family” was of two children, the Tinsleys adopted a second child in 1968. Whenever she could arrange child care, Beatrice continued studying on her own. There was still no prospect of work in Dallas but she presented papers at American Astronomical Society meetings at the University of Colorado at Boulder in 1970 and the University of Massachusetts at Amherst in 1971, with a grant from the National Science Foundation enabling her to pay for some child care and travel to meetings. Tinsley very much reemerged as a researcher in 1971 and 1972 and in these years she published eleven papers.
James Gunn of the California Institute of Technology (Caltech) arranged for a three-month appointment for her at Pasadena in 1972, the first professional opportunity of her life. With her children living with her, she felt fulfilled and energized. Richard Larson of Yale University and Sandra Faber of Lick Observatory joined Gunn at this time in being among the first to perceive her abilities. They were all to become lifelong friends and colleagues. In particular, when collaborating with Gunn and later with Larson, she enjoyed an intense intellectual relationship of the kind she had never before experienced.
Back as a housewife again in Dallas, Beatrice resumed working with Gunn on the first of many important collaborations, and on a research project with the Frenchman Jean Audouze. She also worked on a proposal for an astronomy department at the University of Texas at Dallas (UTD), with a program leading to a master’s degree. This, she hoped, might give her a work opportunity as her husband was becoming adamant that he would not look for a post elsewhere; at UTD he was well respected and secure. Other centers began to vie for her, and in 1973 the University of Maryland offered a visiting lectureship for eighteen months. Beatrice was elated but her husband objected, saying her place was with him in Dallas—this although he would often be away himself during that time, to meetings and on spectroscopy work. He did agree to her taking the children for six months, and another period of creativity opened up for her. Having arranged child care, she continued to accept invitations to speak at other centers, including a part-time position as assistant professor at UTA.
The Tinsleys’ marital relationship was becoming increasingly strained with Beatrice growing ever more frustrated at the lack of scientific opportunities that the marriage implied. They divorced in 1974 and while she had the children for all their holidays, for her the separation from them meant lifelong trauma.
Her mother had died and her father in New Zealand had remarried, but Beatrice still felt impelled to protect him from distress. Now her divorce devastated him. She could offer only a crumb of comfort in the fact that she had been awarded the Annie J. Cannon Prize in Astronomy. This prize, for outstanding research and promise by a postdoctoral woman researcher, is given to a North American female astronomer within five years of receiving her PhD in the year of the award.
Professional Life. At the beginning of 1975 Tinsley accepted a six-month appointment at Lick Observatory before taking up an assistant professorship at Yale. This was prefaced by the first of what became regular summer working visits to Cambridge, England, to the NATO Advanced Study Institute. Here she worked with some of the world leaders in her field. The eminent astronomer and cosmologist Fred Hoyle had been her childhood hero and his books had introduced her to cosmology; she took time away from Cambridge to give the scene-setting review of cosmology at his sixtieth birthday celebrations, held in Venice.
After her arrival at Yale in September 1975, the Yale astronomy department entered an outstanding period. She both unified and electrified the department by bringing together two of its strongest areas, stellar evolution and galactic studies, through outstandingly fruitful collaborations with Larson. Her years at Yale saw something of a shift in her research, as she now pressed the study of galaxies not just as the means to better test cosmological models but as a crucial subject in its own right, too. Responding to the ideas of various theorists, she also examined how the mergers of galaxies might affect their brightnesses.
To further the study of the evolution of galaxies, Tinsley and her colleagues at Yale organized what became known as the Yale International Conference on the Evolution of Galaxies and Stellar Populations. She invited the outstanding people in the field worldwide. Held on 19–21 May 1977, it became one of the most memorable conferences in the lifetimes of its participants and would become widely regarded as a sort of watershed, as it marked the maturing of a field that had previously been largely concerned with classification. As it would come to be remembered, nearly everyone came with the view that galaxies were individuals in the universe whose lives were entirely influenced by their own internal dynamics. Everyone left knowing that galaxies existed in a universe full of other galaxies, and that their interactions among themselves were every bit as important as their internal interactions. Gunn was later to summarize: “It was the single most important galaxy conference in the history of the subject. There has been no other similar conference. There is no Beatrice” (Catley, 2006, p. 297; Gunn to author, September 2001). From the day the conference ended, Tinsley had three years and ten months to live.
Energized by the conference and the children’s holidays with her, she embarked on many projects, using every minute. She continued with her own papers and existing collaborations, and played more chamber music with Larson and a new graduate student, Linda Stryker, who was to become a part-substitute for her much-loved sister, Rowena Hill, a professor of English in Venezuela. Her feminist views led her to sit on relevant Yale committees; she regretted abandoning her maiden name when she married, and counseled women students about this. Always much sought after as a teacher, in spite of the rapidity of her speech sounding like “a stream of dried peas on a windowpane,” she invited a stream of “greats” in their fields to visit her department. Scientific ideas and possibilities seemed unlimited (Catley, 2006, p. 275). In the view of at least one of her collaborators, the Yale International Conference on the Evolution of Galaxies and Stellar Populations also marked Tinsley’s emergence as a true insider in the astronomical community.
Illness. Then, in early 1978, melanoma was diagnosed in her left upper leg. An operation revealed only a fifty-fifty chance of survival. Larson, with whom she had a close relationship, became her mainstay. After initial devastation she realized she must help everyone to cope with her cancer. Her postgraduate students and her children became her first priority. She continued teaching and research as her doctors, realizing the kind of patient she was, fitted in her numerous treatments as much as possible around her scientific activities in New Haven, the wider United States, and abroad. In July 1978 she became a full professor with tenure.
Another change in her personal circumstances came about the next year. Her daughter Teresa had always been hyperactive. Brian Tinsley had married again, and now the Dallas family decided they could no longer cope. The child, aged eleven, was sent to New Haven to live with Beatrice, who by now was suffering extensively from her cancer’s side effects. Larson was again her main support, becoming a virtual father to the child, and moving into her apartment to care for mother and daughter. Her son Alan came to visit and everyone rallied to help.
In November 1980 came what they had dreaded, a brain tumor. Beatrice was left partially paralyzed but she rallied and worked on. Her room in the Yale Infirmary became both a social and a work center, with a stream of students and colleagues. Her joy in scientific endeavor, whether her own or that of others, continued throughout her illness. She taught herself to print with her left hand and in this way, plus dictation, she finished several papers in the infirmary, composed testimonials for her students to be used after her death, and kept up a flow of responses to her wide-ranging correspondents.
Her last thoughts were of her children, as she told astronomer Audouze when he telephoned her from Paris just before she died on 23 March 1981, aged forty (Catley, 2006, pp. 402–403; Audouze to author, July 2001).
Faber, her close friend and colleague, was asked to put into the simplest possible words, for nonscientists attending her funeral, what Tinsley had done and would continue to do for astronomy. She said that Tinsley’s thesis, together with the many increasingly detailed papers she wrote on this and other related subjects over the next fourteen years, had had a profound impact on the course of cosmological studies. The redshift-magnitude test and other similar observations of distant galaxies that for decades had been reckoned to be pivotal cosmological tools had now come to be viewed as even more fertile means for studying galactic evolution. Her work had thus been instrumental in opening up an active and ongoing new field of research.
“More than any other single individual over the last decade, she succeeded in illuminating and unifying the complex processes which together constitute galactic evolution,” Faber wrote in Physics Today (1981, pp. 110–111). She went on to mention the many concepts that Tinsley either originated or played a significant role in developing, which included, among others, the evolution of matter via nucleosynthetic processes and the importance of the physics of highly evolved stars in understanding the integrated properties of galaxies. “Any one of these diverse topics would provide ample material for years of study,” Faber concluded, “but Beatrice Tinsley was highly regarded for her intimate familiarity with all of them.”
WORKS BY TINSLEY
“Evolution of the Stars and Gas in Galaxies.” Astrophysical Journal 151 (1968): 547–565.
“Galactic Evolution: Program and Initial Results.” Astronomy and Astrophysics 20 (1972): 383–396.
“Stellar Evolution in Elliptical Galaxies.” Astrophysical Journal 178 (1972): 319–336.
With J. Richard Gott, James E. Gunn, et al. “An Unbound Universe?” Astrophysical Journal 194 (1974): 543–553.
With James E. Gunn. “Evolutionary Synthesis of the Stellar Population in Elliptical Galaxies. I. Ingredients, Broad-Band Colors, and Infrared Features.” Astrophysical Journal 203 (1976): 52–62.
With G. A. Shields. “Composition. Gradients Across Spiral Galaxies. II. The Stellar Mass Limit.” Astrophysical Journal 203 (1976): 66–71.
With Jean Audouze. “Chemical Evolution of Galaxies.” Annual Review of Astronomy and Astrophysics 14 (1976): 43–79.
With Richard B. Larson. “Star Formation Rates in Normal and Peculiar Galaxies.” Astrophysical Journal 219 (1978): 46–59.
———. “Chemical Evolution and the Formation of Galactic Disks.” Astrophysical Journal 221 (1978): 554–561.
“Evolutionary Synthesis of the Stellar Population in Elliptical Galaxies. II. Late M Giants and Composition Effects.” Astrophysical Journal 222 (1978): 14–22.
With Curtis Struck-Marcell. “Star Formation Rates and Infrared Radiation.” Astrophysical Journal 221 (1978): 562–566.
“Stellar Lifetimes and Abundance Ratios in Chemical Evolution.” Astrophysical Journal 229 (1979): 1046–1056.
“Evolution of the Stars and Gas in Galaxies.” Fundamentals of Cosmic Physics 5 (1980): 287–388.
“On the Interpretation of Galaxy Counts.” Astrophysical Journal 241 (1980): 41–53.
With Chi-Chao Wu, Sandra M. Faber, et al. “The Ultraviolet Continua of the Nuclei of M31 and M81.” Astrophysical Journal 237 (1980): 290–302.
With Richard B. Larson and C. Nelson Caldwell. “The Evolution of Disk Galaxies and the Origin of S0 Galaxies.” Astrophysical Journal 237 (1980): 692–707.
With James E. Gunn and Linda L. Stryker. “Evolutionary Synthesis of the Stellar Population in Elliptical Galaxies. III. Detailed Optical Spectra.” strophysical Journal 249 (1981): 48–67.
Catley, Christine Cole. Bright Star: Beatrice Hill Tinsley, Astronomer. Auckland, New Zealand: Cape Catley, 2006.
Eisberg, Joann. “Making a Science of Observational Cosmology: The Cautious Optimism of Beatrice Tinsley.” Journal for the History of Astronomy 32 (2001): 263–278.
Faber, Sandra. “Beatrice Tinsley.” Physics Today 34 (1981): 110–111.
Hill, Edward. My Daughter Beatrice, a Personal Memoir of Dr. Beatrice Tinsley, Astronomer. New York: American Physical Society, 1986.
Larson, Richard B., and Linda Stryker. “Obituary, Beatrice Muriel Hill Tinsley.” Quarterly Journal of the Royal Astronomical Society 23 (1982): 162–165.
Overbye, Dennis. Lonely Hearts of the Cosmos. New York: HarperCollins, 1991.
Trimble, Virginia. “Beatrice M. Tinsley.” In Visit to a Small Universe. New York: American Institute of Physics, 1992, pp. 285–293.
Christine Cole Catley