November 3, 1916–August 31, 2000
BY EUGENE N. PARKER
JOHN SIMPSON WAS A visionary experimental nuclear and cosmic ray physicist, a prolific inventor, a vigorous booster of colleagues and university, and was deeply committed to communicating science and its implications to the public and political leaders. His eyes were continually on the next generation of science as he worked with the present tasks, anticipating the next leap forward. Thus his specific scientific measurements invariably had profound implications.
Simpson began his professional career in 1943 as a group leader on the Manhattan Project. He recognized the social and human implications of nuclear energy for both sustained and explosive release, and he and many others of the project began serious discussion of the future of nuclear energy and the human relation to it. Such group discussions were forbidden under the wartime regulations imposed on the project, but the ideas were developed and shared among the concerned scientists nonetheless. The upshot was that John Simpson became a founding member and first chairman of the Atomic Scientists of Chicago, formally founded August 7, 1945, the day after the United States dropped the atomic bomb on Hiroshima. He was a cofounder of the Bulletin of the Atomic Scientists later in 1945. The doomsday clock on the cover of the bulletin is familiar to all. Henry