Harrison Brown

Harrison Scott Brown (September 26, 1917 – December 8, 1986) was an American nuclear chemist and geochemist. He was a political activist, who lectured and wrote on the issues of arms limitation, natural resources and world hunger.

During World War II, Brown worked at the Manhattan Project's Metallurgical Laboratory and Clinton Engineer Works, where he worked on ways to separate plutonium from uranium. The techniques he helped develop were used at the Hanford Site to produce the plutonium used in the Fat Man bomb dropped on Nagasaki. After the war he lectured on the dangers of nuclear weapons.

After the war, he worked at the University of Chicago, where he pioneered nuclear geochemistry. The study of meteorites by Brown and his students led to the first close approximation of the age of the Earth and the solar system. Between 1951 and 1977, he worked at the California Institute of Technology (Caltech) where he contributed to advancements in telescopic instrumentation, jet propulsion, and infrared astronomy.

Early life
Harrison Scott Brown was born in Sheridan, Wyoming, on September 26, 1917, the son of a rancher and cattle broker, Harrison H. Brown (1880-1927), and his wife Agnes Anna (Scott) Brown (1889-1963), a piano teacher from Dubuque, IA. His father died when he was just ten years old and the family moved to San Francisco, where his mother worked as a dental assistant, and played the piano for silent movie theaters. He learned to play piano and formed a jazz band, but never learned how to read music notation. He attended Galileo High School, and entered the University of California, Berkeley, where he earned a bachelor of science (B.S.) degree in chemistry in 1938. He married Adele Scrimger, with whom he had a son, Eric Scott Brown.

While at Berkeley, Brown had become interested in nuclear chemistry. He moved to Johns Hopkins University in Baltimore, Maryland, where he studied for his doctorate under the supervision of Robert D. Fowler, who had been a chemistry professor at Berkeley from 1930 to 1936. For his doctorate, Brown constructed a mass spectroscope. Following the discovery of nuclear fission by Lise Meitner and Otto Hahn in 1939, there arose considerable interest in. Brown and Fowler studied the properties of uranium hexafluoride, which they were soon supplying to Columbia University and the University of Chicago, where research was being conducted into isotope separation for what would become the Manhattan Project. In 1941 he was awarded his doctor of philosophy (Ph.D.) by Johns Hopkins University, writing his thesis in two topics that would be of great interest to the Manhattan Project :the construction of a mass spectrometer for isotope analysis, and the thermal diffusion of argon.

Manhattan Project
In 1942 Glenn T. Seaborg invited Brown to work with him at the University of Chicago in the Manhattan Project's Metallurgical Laboratory, working on ways to separate plutonium from uranium. The Manhattan Project intended to create plutonium by irradiating uranium in a nuclear reactor. The resulting highly radioactive product would then have to be chemically separated from the uranium and any fission products created by the irradiation process. The problem was that plutonium was a new element with chemical properties that were not yet fully known. Until a reactor could be built, it was available only in microgram amount, so an industrial separation process would have to be scaled up one billion times. With Orville Hill, Brown devised a successful method of achieving this by using the gaseous evaporation of fluorides.

Brown and some of his colleagues to the Oak Ridge, Tennessee, to work with the X-10 Graphite Reactor at Clinton Engineer Works, where he became the assistant director of chemistry. Working with the reactor there, they developed the separation processes for producing kilogram quantities of plutonium. The techniques discovered by the team proved to be the groundwork for those used at the Hanford Site which provided the plutonium for the Fat Man bomb dropped on Nagasaki on August 9, 1945. Just four months later he completed Must Destruction Be Our Destiny? (1945), a book detailing the dangers of nuclear weapons. He gave 102 lectures to promote the book, donating the royalties from the book to an organisation that later became part of the Federation of American Scientists.

Later life
In 1946, Brown returned to the University of Chicago to work as an assistant professor of Chemistry in the Institute for Nuclear Studies. He was joined by some of his former colleagues from the Manhattan Project and together they became the first team to study nuclear geochemistry. He went on to study meteorites and planetary structures along with ways to date the age of the Earth, encouraging his George Tilton and Clair Cameron Patterson to investigate the isotopic composition of iron meteorites. Patterson's studies of lead eventually led to the first close approximation of the age of the Earth and the solar system of 4.5 billion years. Another of his doctoral students, Edward D. Goldberg, measured trace occurrences of gallium, gold, palladium, and rhenium in meteorites, he was able to group iron meteorites based on their geochemical composition. In 1948 Brown was awarded the American Association for the Advancement of Science prize for his work on meteorites.

Between 1951 and 1977, Brown was professor of geochemistry at the California Institute of Technology (Caltech). While there he attracted several former colleagues and highly regarded scientists to the team. Together they made advancements in telescopic instrumentation, jet propulsion (contributing to NASA's early planetary exploration missions), and infrared astronomy.

Brown joined the National Academy of Sciences in 1955 and was appointed as their foreign secretary in January 1962, a role that he would hold until 1974. He demonstrated an interest in the scientific interactions between the United States and Eastern Europe. Len Ackland noted that "Geochemistry and his travels in developing countries caused him to ponder the adequacy of the Earth`s resources and the problems of development, hunger and population growth." These were themes that he would expound on in his next three books: The Challenge of Man's Future (1954), The Next Hundred Years (1957) and The Human Future Revisited (1978). He also wrote a science fiction novel, The Cassiopeia Affair with Chloe Zerwick. He divorced Adele and married Rudd Owen, who collaborated with him on his writings and social activism. "Man has it within his power today," he said in 1976, "to create a world in which people the world over can lead free and abundant and even creative lives. I am convinced that we can create a world which will pale the Golden Age of Pericles into nothingness."

In 1983 Brown retired and moved yo Albuquerque, New Mexico with his third wife, Theresa Tellez, his second marriage having also ended in divorce. He became a regular columnist and editor-in-chief of the Bulletin of the Atomic Scientists. In his last years, Brown battled lung cancer, the treatment for which had resulted in progressive paralysis through the irradiation of his spine. He died in the University of New Mexico Hospital in Albuquerque on December 8, 1986. He was survived by his third wife, Theresa, and his son Eric.

Selected publications

 * Must Destruction Be Our Destiny? (1945)
 * The Challenge of Man's Future (1954)
 * The Next Hundred Years (1957)
 * The Cassiopeia Affair with Chloe Zerwick (1968)
 * The Human Future Revisited (1978)