Darleane C. Hoffman

Born on 8 November 1926 in Terril, Iowa, Darleane C. Hoffman is a nuclear chemist who has studied transuranium elements in nature and in the lab. She entered Iowa State College as an art major; by the time she left, she had received her bachelor’s and doctoral degrees in chemistry. She then went to work in nuclear chemistry at Los Alamos National Laboratory in New Mexico. Hoffman made her mark studying atoms of some of the heaviest elements on the periodic table. In 1971 she discovered plutonium in billion-year-old rock, proving that small amounts of elements heavier than uranium occur in nature. She made important observations of atoms of dubnium and lawrencium, which decay in a matter of minutes or seconds. And she discovered that atoms of the element fermium (atomic number 100) can undergo nuclear fission spontaneously, without being bombarded by a particle such as a neutron. Hoffman then moved to the University of California, Berkeley, and the Lawrence Berkeley National Laboratory, where she discovered new superheavy elements with Glenn Seaborg. She has also investigated safety procedures at nuclear weapon test sites and radioactive waste storage facilities. Hoffman was awarded the National Medal of Science in 1997. (Photo credit: Lawrence Berkeley National Laboratory)

Date in History: 8 November 1926