User:Claydonald/Donald D. Clayton

Donald D. Clayton: a brief biography

In 2010 Donald D. Clayton is 75 years old. He was born in 1935 into a farming community to parents who had been born on their family farms in southwestern Iowa. In the middle of the great depression his father left the family farm to start flying small aircraft and later moved his young family to Dallas, Texas to take better and steady work as an airline pilot with Braniff Airways. This leaving of the family farms of Adair County, Iowa produced an early sense of grief and loss in young Donald (then five years old). This sense of loss haunted him for decades.

The Clayton family was fortunate to purchase a new home on 1941 that lay on the outskirts of University Park and was accepted into the University Park school system despite not being a resident of the Park Cities. This soon to be legendary school system in the state of Texas provided for young Donald the excellent education and upward spirit that was exceptional in the history of his extended Iowa family. Graduation from Highland Park High School in January 1953 had exposed him to mathematics, physics and chemistry far beyond the typical experience of his farming relations. He then became the first of all of his relations to attend university, Southern Methodist University in Dallas. Showing exceptional gifts, he was invited to major in physics by the chairman of its physics department, who also created a laboratory teaching job that made that major financially possible. That Chairman and Professor later changed the author’s entire life by suggesting that he attempt graduate school in physics at the famed California Institute of Technology. Before graduation from SMU Clayton married another 19-year-old from his high school, and in innocent naiveté they moved in 1956 to Pasadena CA and legendary Caltech. Doing so made his scientific life possible.

Clayton became fascinated at Caltech with Hoyle's new idea that the atoms of the chemical elements were assembled by nuclear reactions within dying stars, from which they were expelled. Thanks to good performance in the graduate course in nuclear physics, Clayton was accepted by the professor, William A. Fowler, as his graduate student. This suited Fowler’s goal of making the nuclear physics lab, Kellogg Radiation Laboratory, into a center for study of the origin of the elements. Clayton's research on nucleosynthesis began in 1957, the year of the publication by Fowler and coauthors of a famous review paper on nucleosynthesis, coauthored with Fred Hoyle, who had created the stellar theory. Clayton's PhD thesis formulating the time-dependent s process was defended in August 1961. Clayton’s seminal works in that discipline while at Caltech involved first formulations of the change of abundances with time for three major processes of nucleosynthesis (s process, r process, silicon burning), as well as inventing a new nuclear clock (187Re decay) for the age of the chemical elements. These won him fame and stature as a pioneer of the new scientific discipline of stellar nucleosynthesis. At the same time his first two sons were born in Pasadena, but his marriage declined.

Following two postdoctoral research years (1961-63) at Caltech, Clayton moved in 1963 to position of Assistant Professor in the new Department of Space Science at Rice University in Houston. That modern department was created to fit the mood of hosting the new Manned Spacecraft Center in Houston. At Rice University Clayton initiated a graduate course in the physical principles of the evolution of the stars and of the creation of the atoms of the elements in the stars. This became a famous textbook, Principles of Stellar Evolution and Nucleosynthesis(McGraw-Hill, New York 1968), published in 1968 and still used today. With excellent research students and two new faculty hires, Clayton built by 1970 the premier nucleosynthesis school in the United States, supplanting Caltech’s earlier leadership. Responding to an invitation from Fred Hoyle (supported by Fowler), Clayton agreed in 1967 to become nucleosynthesis coordinator of Hoyle’s newly formed Institute of Theoretical Astronomy in Cambridge UK. Clayton resided in Cambridge about 1/3 time during the next seven years. In the middle of that period, he introduced an exciting new astronomy of radioactivity in order to test nucleosynthesis by detecting the gamma rays emitted by freshly created radioactivity in exploding stars. His leadership of that expectation led him to become a Co-Investigator on NASA’s Gamma Ray Observatory, which did successfully detect radioactive nuclei two decades later.

A seven-year period followed in Heidelberg, where Clayton accepted an honorary position (Alexander von Humboldt Senior Scientist, 1976-82) to develop his new theory of stardust. The theory focused initially on isotopically anomalous solids that he predicted to condense from hot gas within the expanding and cooling supernova interior. It predicted that solid grains that condense, using newly created heavy elements, from hot vapor in dying stars could be recognized by their wildly unusual isotopic compositions for the chemical elements from which they condensed. His predictions laid the basis for a second exciting new field of astronomy, revealing the physics of stars and of nucleosynthesis from the isotopic ratios measured within the stardust. So much controversial resistance to these ideas was exerted by prominent meteoriticists prior to the discovery of stardust within meteorites that Clayton’s personality was altered by the scrimmage (see his autobiography). Clayton resided half time for this seven-year period in Heidelberg.

Clayton remarried Nancy McBride in 1983 in Houston at Rice University. Their marriage brought a heretofore unknown peace and mutual care, creating the happiest personal phase of Clayton’s life. The associated sense of a new start prompted them to also seek a new university position where Clayton could be of value and where life did not carry so much historical baggage. To that end he brought his Gamma Ray Observatory program Co-Investigator, Oriented Scintillation Spectrometer Experiment (OSSE), aboard Compton Gamma Ray Observatory, launched 1991 by Shuttle Atlantis to Clemson University, where they now live. Clayton centered the buildup of astrophysics at Clemson University on Compton GRO and on stardust in meteorites.

Among Clayton's many honors are Leonard Medal (Meteoritical Society 1991), NASA Exceptional Scientific Achievement Medal (1993), Fellow American Academy of Arts and Sciences (2000).

Clayton has published a scientific autobiography CATCH A FALLING STAR (iUniverse, Indianappolis 2009). It elaborates his scientific life much more fully. See www.claytonstarcatcher.com