John Simpson died at age 83 in Chicago on 31 August 2000 from pneumonia following successful heart surgery. He was renowned as a nuclear and cosmic-ray physicist. At the University of Chicago he was the Arthur H. Compton Distinguished Service Professor emeritus at the Enrico Fermi Institute and the Department of Physics.
Simpson was born on 3 November 1916 in Portland, Oregon. He received an AB degree in physics from Reed College in 1940. At New York University he earned an MS degree in physics in 1942 and his PhD in 1943.
Simpson was one of the 12 scientists who organized the program of the 1957-1958 International Geophysical Year to study cosmic rays, solar physics, and magnetospheric physics. In the course of his career he sponsored 34 PhD students, many of whom are now leaders in the space sciences.
Eugene Parker of the University of Chicago prepared a full obituary for Simpson that was published in Physics Today, December 2000.
Photograph courtesy of the University of Chicago News Office