Mills was born in
Estes Park, Colorado to Enoch and Ethel Mills. Prior to college he attended Estes Park High School and then moved to
Ft. Lauderdale High School,
Florida. He received his
B.S. from the
California Institute of Technology in 1940. During
World War II, he served as a physicist at the
Jet Propulsion Laboratory, heading up the solid propellant section. He was also a physics instructor and lectured for the aeronautics department at Caltech. It was during the war in 1942 that he married Pauline Riedeburg. He completed his
Ph.D. in physics from Caltech in 1948. Following his graduation he started working at
North American Aviation, performing theoretical work in their atomic energy research department. He and his colleagues made valuable contributions in the field of
nuclear reactor technology. In 1951 he became technical director at
Project SQUID at
Princeton University, where basic research was performed in aircraft propulsion. In 1952 he returned to his work in reactor design at North American. In 1954 he joined the radiation laboratory at the University of California, becoming head of the theoretical division. By 1955 he was a part-time lecturer at the university, on the subject of nuclear reactor theory. He also helped organize the nuclear engineering program at the institution. He would become a professor of Nuclear Engineering at the university in 1957. He was also made chairman of the school's division of
nuclear engineering. In 1958 he took a leave of absence to become deputy director of the Livermore radiation laboratory at the University of California. It was during this period that he was killed during an accident at the Eniwetok Proving Ground, located on the
Eniwetok Atoll in the
Marshall Islands. He was flying in a
helicopter that was forced down as a result of torrential rain. This accident occurred during the preparations for a series of
atomic bomb tests. Dr. Mills and his wife had two children, Mark John and Ann. ==Awards and honors==