Harold Urey

Urey married Frieda in 1926 at Lawrence, Kansas. The couple was blessed with four children, Gertrude Bessie (Elisabeth) in 1927, Frieda Rebecca in 1929, Mary Alice in 1934 and John Clayton Urey in 1939.

He breathed his last on January 5, 1981, at La Jolla, California. He was buried at the Fairfield Cemetery in DeKalb County, Indiana.

A lunar impact crater and asteroid 4716 has been named after him.

Harold Urey was born as Harold Clayton Urey to Samuel Clayton Urey and Cora Rebecca née Reinoehl on April 29, 1893 in Walkerton, Indiana. He was the eldest child of the couple and two had younger siblings, a brother and sister. His father passed away when Urey was six.

Young Urey gained his early education from Amish Grade School before enrolling at a high school in Kendallville, Indiana. He obtained a teacher’s certificate from the Earlham College.

In 1914, Urey enrolled himself at the University of Montana in Missoula. Three years later, he graduated with a Bachelor’s degree in Zoology. Same year, US entered World War I. Urey took a wartime job with Barrett Chemical Company, making TNT.

Post World-War I, he took up job as an instructor in Chemistry at the University of Montana. In 1921, he enrolled for a PhD program at the University of California, Berkeley, where he studied thermodynamics. His work led to accepted methods for calculating thermodynamic properties from spectroscopic data.

Upon completing his PhD in 1923, Urey gained a fellowship by the American-Scandinavian Foundation to study at the Niels Bohr Institute in Copenhagen under the Danish physicist.

Returning to United States, he received two offers - a fellowship to Harvard University and a research associate at Johns Hopkins University. He chose the latter.

In 1929, he was appointed as an associate professor of Chemistry at the Columbia University. Following year, along with Arthur Ruark, Urey penned ‘Atoms, Quanta and Molecules’. The book was one of the first written works on quantum mechanics and its application to atomic and molecular system.

During the 1930s, the theory of isotopes had been developed. Chemists from around the world were aware that an element may consist of atoms with the same number of protons but different masses. While the isotopes of carbon, nitrogen and oxygen had been discovered, the discovery of the isotopes of hydrogen remained a mystery. As such, Urey set forth himself to find out the isotopes of hydrogen.

Harold Urey is best remembered as the world expert on isotope separation. His pioneering work came during the 1930s and 1940s decade when he started working on separation of isotopes. It was due to his rigorous experimental work that finally deuterium, an isotope of hydrogen was discovered. During World War II, he dedicated himself to isotope separation of uranium and uranium enrichment. He successfully developed the same using the method of gaseous diffusion.