Stein Bjornar Jacobsen (born 1950)[1] is a Norwegian-American geochemist who works within cosmochemistry.
degree at the University of Oslo before studying geology in California with a Rotary grant.
[2] Jacobsen became a professor of geochemistry at Harvard University.
[3] He was an inducted into the Norwegian Academy of Science and Letters in 1994.
[1] In 2009 he was inducted into the American Academy of Arts and Sciences, mainly for using "the distribution of long-lived and extinct radioisotopes to date the formation of the earth's core and to define the effects of core separation on the early history of the core-mantle-crust system".