Harold Clayton Urey (1893-1981) discovered the heavy hydrogen in the 1930s.
Heavy hydrogen, or deuterium, was discovered by Harold Urey in December 1931 through experiments that identified it by its spectral lines. Urey's work led to him receiving the Nobel Prize in Chemistry in 1934. Deuterium is important in various scientific applications due to its unique properties as an isotope of hydrogen.
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