Harold Urey found heavy hydrogen and offered to fly one way to the Moon
Harold Urey won the 1934 Nobel Prize in Chemistry for discovering deuterium, the heavy form of hydrogen. Decades later, when Apollo astronauts brought back lunar rock, he examined it himself. The astronaut Harrison Schmitt recalled that Urey once volunteered to go to the Moon even if he could never come back.
Urey was born in 1893 in Walkerton, Indiana, the son of a teacher and Church of the Brethren minister who died of tuberculosis when Harold was six. He finished an Amish grade school at 14, taught in rural schoolhouses in Indiana and Montana, and took a zoology degree at the University of Montana in 1917. Raised in a sect opposed to war, he spent the First World War making TNT at a Philadelphia chemical plant rather than serving as a soldier.
He earned his doctorate at Berkeley under Gilbert N. Lewis, after abandoning a first thesis when the Indian physicist Meghnad Saha published a better paper on the same topic. A fellowship took him to Niels Bohr's institute in Copenhagen, where he met Heisenberg and Pauli. At Johns Hopkins he co-wrote one of the first English textbooks on quantum mechanics, and in 1929 he moved to Columbia.
Isotopes were still poorly understood; the neutron was not found until 1932. Comparing oxygen's atomic weight with hydrogen's, two Berkeley scientists had predicted that roughly one hydrogen atom in 4,500 was heavy. In 1931 Urey set out to concentrate and detect it, and succeeded. During the Second World War he applied that expertise to uranium, leading the Columbia group that developed enrichment by gaseous diffusion, which became the only method used in the early postwar years.
At the University of Chicago he proposed that Earth's early atmosphere held ammonia, methane and hydrogen. His graduate student Stanley Miller zapped such a mixture with sparks in the presence of water and produced amino acids, building blocks of life. Urey's measurements of oxygen isotopes also founded the study of ancient climates. In 1958 he moved to the new University of California, San Diego, helping build its science faculty, and he died in 1981.
Source: Harold Urey
