Harold Clayton Urey (29.04.1893 — 1981) was an American physicist and physical chemist and a member of the National Academy of Sciences (1935). He was born in Walkerton. He graduated from the University of Montana (1917) and taught there in 1919-21. In 1924-29 he worked at Johns Hopkins University and in 1929—45 at Columbia University (professor from 1934), where in 1940—45 he headed the research laboratory for the separation of uranium isotopes. In 1945 —58 he was professor at the Enrico Fermi Institute for Nuclear Studies of the University of Chicago, and in 1958 —70 at the University of California (San Diego).
His work was in atomic physics, spectroscopy, quantum mechanics, isotope chemistry, geochemistry and cosmochemistry. In 1932 he discovered heavy hydrogen and named it deuterium (Nobel Prize in Chemistry, 1934). He carried out research on the production of heavy water and the separation of uranium isotopes, in particular in order to obtain uranium-235.
In the post-war years Urey's scientific interests were concentrated in geochemistry and cosmochemistry. He measured the palaeotemperatures of Cretaceous belemnites, which was one of the notable successes of geophysics. He worked on the development of a new field, the geochemistry of stable isotopes, and studied problems of astrophysics, geochronology and the origin of life. He proved (1950) that amino acids are formed by electrical discharges in the atmosphere. His book “The Planets: Their Origin and Development”, published in 1952, contained the first systematic chronology of the Solar System. His research also concerned the origin of meteorites, the structure of the Moon, and the distribution and origin of the elements and their isotopes in nature. In 1956, together with H. Suess, he drew up a table of the relative abundance of the chemical elements.
A member of many academies of sciences and learned societies. The J. Gibbs Medal (1934), the H. Davy Medal (1940), the B. Franklin Medal (1943), the National Medal of Science (1964) and others.