Harold Clayton Urey ( ; April 29, 1893 – January 5, 1981) was an American
physical chemist
Physical chemistry is the study of macroscopic and microscopic phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical me ...
whose pioneering work on
isotope
Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) ...
s earned him the
Nobel Prize in Chemistry
)
, image = Nobel Prize.png
, alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "M ...
in 1934 for the discovery of
deuterium
Deuterium (or hydrogen-2, symbol or deuterium, also known as heavy hydrogen) is one of two Stable isotope ratio, stable isotopes of hydrogen (the other being Hydrogen atom, protium, or hydrogen-1). The atomic nucleus, nucleus of a deuterium ato ...
. He played a significant role in the development of the
atom bomb
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or a combination of fission and fusion reactions (thermonuclear bomb), producing a nuclear explosion. Both bomb ...
, as well as contributing to theories on the
development of organic life from non-living matter.
Born in
Walkerton, Indiana
Walkerton is a town in Lincoln Township, St. Joseph County, in the U.S. state of Indiana. The population was 2,144 at the 2010 Census. It is part of the South Bend–Mishawaka, IN- MI, Metropolitan Statistical Area.
History
Walkerton was pl ...
, Urey studied
thermodynamics
Thermodynamics is a branch of physics that deals with heat, work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these quantities is governed by the four laws of the ...
under
Gilbert N. Lewis
Gilbert Newton Lewis (October 23 or October 25, 1875 – March 23, 1946) was an American physical chemist and a Dean of the College of Chemistry at University of California, Berkeley. Lewis was best known for his discovery of the covalent bond a ...
at the
University of California, Berkeley
The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...
. After he received his
PhD PHD or PhD may refer to:
* Doctor of Philosophy (PhD), an academic qualification
Entertainment
* '' PhD: Phantasy Degree'', a Korean comic series
* ''Piled Higher and Deeper'', a web comic
* Ph.D. (band), a 1980s British group
** Ph.D. (Ph.D. albu ...
in 1923, he was awarded a fellowship by
the American-Scandinavian Foundation
The American-Scandinavian Foundation (ASF) is an American non-profit foundation dedicated to promoting international understanding through educational and cultural exchange between the United States and Denmark, Finland, Iceland, Norway
...
to study at the
Niels Bohr Institute
The Niels Bohr Institute (Danish: ''Niels Bohr Institutet'') is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics. ...
in
Copenhagen
Copenhagen ( or .; da, København ) is the capital and most populous city of Denmark, with a proper population of around 815.000 in the last quarter of 2022; and some 1.370,000 in the urban area; and the wider Copenhagen metropolitan ar ...
. He was a research associate at
Johns Hopkins University
Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hem ...
before becoming an associate professor of Chemistry at
Columbia University
Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...
. In 1931, he began work with the separation of isotopes that resulted in the discovery of deuterium.
During World War II, Urey turned his knowledge of isotope separation to the problem of
uranium enrichment
Enriched uranium is a type of uranium in which the percent composition of uranium-235 (written 235U) has been increased through the process of isotope separation. Naturally occurring uranium is composed of three major isotopes: uranium-238 (238U ...
. He headed the group located at Columbia University that developed isotope separation using
gaseous diffusion
Gaseous diffusion is a technology used to produce enriched uranium by forcing gaseous uranium hexafluoride (UF6) through semipermeable membranes. This produces a slight separation between the molecules containing uranium-235 (235U) and uranium-2 ...
. The method was successfully developed, becoming the sole method used in the early post-war period. After the war, Urey became professor of chemistry at the
Institute for Nuclear Studies
__NOTOC__
The Institute for Nuclear Studies was founded September 1945 as part of the University of Chicago with Samuel King Allison as director. On November 20, 1955, it was renamed The Enrico Fermi Institute for Nuclear Studies. The name was sh ...
, and later Ryerson professor of chemistry at the
University of Chicago
The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...
.
Urey speculated that the early terrestrial
atmosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...
was composed of
ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...
,
methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Eart ...
, and hydrogen. One of his Chicago graduate students was
Stanley L. Miller, who showed in the
Miller–Urey experiment
The Miller–Urey experiment (or Miller experiment) is a famous chemistry experiment that simulated the conditions thought at the time (1952) to be present in the atmosphere of the early, prebiotic Earth, in order to test the hypothesis of the ...
that, if such a mixture were exposed to electric sparks and water, it can interact to produce
amino acids
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...
, commonly considered the building blocks of life. Work with
isotopes of oxygen
There are three known stable isotopes of oxygen (8O): , , and .
Radioactive isotopes ranging from to have also been characterized, all short-lived. The longest-lived radioisotope is with a half-life of , while the shortest-lived isotope is ...
led to pioneering the new field of
paleoclimatic
Paleoclimatology (British spelling, palaeoclimatology) is the study of climates for which direct measurements were not taken. As instrumental records only span a tiny part of Earth's history, the reconstruction of ancient climate is important to ...
research. In 1958, he accepted a post as a professor at large at the new
University of California, San Diego
The University of California, San Diego (UC San Diego or colloquially, UCSD) is a public university, public Land-grant university, land-grant research university in San Diego, California. Established in 1960 near the pre-existing Scripps Insti ...
(UCSD), where he helped create the science faculty. He was one of the founding members of UCSD's school of chemistry, which was created in 1960. He became increasingly interested in space science, and when
Apollo 11
Apollo 11 (July 16–24, 1969) was the American spaceflight that first landed humans on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin landed the Apollo Lunar Module ''Eagle'' on July 20, 1969, at 20:17 UTC, an ...
returned
moon rock
Moon rock or lunar rock is rock originating from Earth's Moon. This includes lunar material collected during the course of human exploration of the Moon, and rock that has been ejected naturally from the Moon's surface and landed on Earth as ...
samples from the moon, Urey examined them at the
Lunar Receiving Laboratory
The Lunar Receiving Laboratory (LRL) was a facility at NASA's Lyndon B. Johnson Space Center (Building 37) that was constructed to quarantine astronauts and material brought back from the Moon during the Apollo program to reduce the risk of ...
. Lunar astronaut
Harrison Schmitt
Harrison Hagan Schmitt (born July 3, 1935) is an American geologist, retired NASA astronaut, university professor, former U.S. senator from New Mexico, and the most recent living person—and only person without a background in military aviation ...
said that Urey approached him as a volunteer for a one-way mission to the Moon, stating "I will go, and I don't care if I don't come back."
Early life
Harold Clayton Urey was born on April 29, 1893, in
Walkerton, Indiana
Walkerton is a town in Lincoln Township, St. Joseph County, in the U.S. state of Indiana. The population was 2,144 at the 2010 Census. It is part of the South Bend–Mishawaka, IN- MI, Metropolitan Statistical Area.
History
Walkerton was pl ...
, the son of Samuel Clayton Urey,
a school teacher and a minister in the
Church of the Brethren
The Church of the Brethren is an Anabaptist Christian denomination in the Schwarzenau Brethren (german: link=no, Schwarzenauer Neutäufer "Schwarzenau New Baptists") tradition that was organized in 1708 by Alexander Mack in Schwarzenau, Germa ...
, and his wife, Cora Rebecca née Reinoehl.
He had a younger brother, Clarence, and a younger sister, Martha. The family moved to
Glendora, California
Glendora is a city in the San Gabriel Valley in Los Angeles County, California, east of Los Angeles. As of the 2020 census, the population of Glendora was 52,558.
Known as the "Pride of the Foothills", Glendora is nestled in the foothills o ...
, after Samuel became seriously ill with
tuberculosis
Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...
, in hopes that the climate would improve his health. When it became clear that he would die, the family moved back to Indiana to live with Cora's widowed mother. Samuel died when Harold was six years old.
Urey was educated in an
Amish
The Amish (; pdc, Amisch; german: link=no, Amische), formally the Old Order Amish, are a group of traditionalist Anabaptist Christian church fellowships with Swiss German and Alsatian origins. They are closely related to Mennonite churches ...
grade school, from which he graduated at the age of 14. He then attended high school in
Kendallville, Indiana
Kendallville is a city in Wayne Township, Noble County, in the U.S. state of Indiana. The population was 9,862 at the 2010 census.
History
Kendallville was laid out in 1849. The city was named for Amos Kendall, 8th United States Postmaster Gene ...
.
After graduating in 1911, he obtained a teacher's certificate from
Earlham College
Earlham College is a private liberal arts college in Richmond, Indiana. The college was established in 1847 by the Religious Society of Friends (Quakers) and has a strong focus on Quaker values such as integrity, a commitment to peace and social ...
,
and taught in a small school house in Indiana. He later moved to Montana, where his mother was then living, and continued to teach there.
Urey entered the
University of Montana
The University of Montana (UM) is a public research university in Missoula, Montana. UM is a flagship institution of the Montana University System and its second largest campus. UM reported 10,962 undergraduate and graduate students in the fal ...
in
Missoula
Missoula ( ; fla, label=Salish language, Séliš, Nłʔay, lit=Place of the Small Bull Trout, script=Latn; kut, Tuhuⱡnana, script=Latn) is a city in the U.S. state of Montana; it is the county seat of Missoula County, Montana, Missoula Cou ...
in the autumn of 1914. Unlike Eastern universities of the time, the University of Montana was co-educational in both students and teachers.
Urey earned a
Bachelor of Science
A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years.
The first university to admit a student to the degree of Bachelor of Science was the University of ...
(BS) degree in
zoology
Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, evolution, Biological clas ...
there in 1917.
As a result of the
United States entry into World War I
United may refer to:
Places
* United, Pennsylvania, an unincorporated community
* United, West Virginia, an unincorporated community
Arts and entertainment Films
* ''United'' (2003 film), a Norwegian film
* ''United'' (2011 film), a BBC Two fi ...
that same year, there was strong pressure to support the war effort. Urey had been raised in a religious sect that opposed war. One of his professors suggested that he support the wartime effort by working as a chemist. Urey took a job with the
Barrett Chemical Company in
Philadelphia
Philadelphia, often called Philly, is the largest city in the Commonwealth of Pennsylvania, the sixth-largest city in the U.S., the second-largest city in both the Northeast megalopolis and Mid-Atlantic regions after New York City. Sinc ...
, making
TNT
Trinitrotoluene (), more commonly known as TNT, more specifically 2,4,6-trinitrotoluene, and by its preferred IUPAC name 2-methyl-1,3,5-trinitrobenzene, is a chemical compound with the formula C6H2(NO2)3CH3. TNT is occasionally used as a reagen ...
, rather than joining the army as a soldier.
After the war, he returned to the
University of Montana
The University of Montana (UM) is a public research university in Missoula, Montana. UM is a flagship institution of the Montana University System and its second largest campus. UM reported 10,962 undergraduate and graduate students in the fal ...
as an instructor in
chemistry
Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...
.
An academic career required a doctorate, so in 1921 Urey enrolled in a
PhD PHD or PhD may refer to:
* Doctor of Philosophy (PhD), an academic qualification
Entertainment
* '' PhD: Phantasy Degree'', a Korean comic series
* ''Piled Higher and Deeper'', a web comic
* Ph.D. (band), a 1980s British group
** Ph.D. (Ph.D. albu ...
program at the
University of California, Berkeley
The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...
, where he studied
thermodynamics
Thermodynamics is a branch of physics that deals with heat, work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these quantities is governed by the four laws of the ...
under
Gilbert N. Lewis
Gilbert Newton Lewis (October 23 or October 25, 1875 – March 23, 1946) was an American physical chemist and a Dean of the College of Chemistry at University of California, Berkeley. Lewis was best known for his discovery of the covalent bond a ...
. His initial attempt at a thesis was on the
ionization
Ionization, or Ionisation is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecule i ...
of
cesium
Caesium (IUPAC spelling) (or cesium in American English) is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of , which makes it one of only five elemental metals that ar ...
vapor. He ran into difficulties, and
Meghnad Saha
Meghnad Saha (6 October 1893 – 16 February 1956) was an Indian astrophysicist who developed the Saha ionization equation, used to describe chemical and physical conditions in stars. His work allowed astronomers to accurately relate the sp ...
published a better paper on the same subject.
Urey then wrote his thesis on the ionization states of an
ideal gas
An ideal gas is a theoretical gas composed of many randomly moving point particles that are not subject to interparticle interactions. The ideal gas concept is useful because it obeys the ideal gas law, a simplified equation of state, and is a ...
, which was subsequently published in the ''
Astrophysical Journal
''The Astrophysical Journal'', often abbreviated ''ApJ'' (pronounced "ap jay") in references and speech, is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and Jame ...
''. After he received his PhD in 1923, Urey was awarded a fellowship by
the American-Scandinavian Foundation
The American-Scandinavian Foundation (ASF) is an American non-profit foundation dedicated to promoting international understanding through educational and cultural exchange between the United States and Denmark, Finland, Iceland, Norway
...
to study at the
Niels Bohr Institute
The Niels Bohr Institute (Danish: ''Niels Bohr Institutet'') is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics. ...
in
Copenhagen
Copenhagen ( or .; da, København ) is the capital and most populous city of Denmark, with a proper population of around 815.000 in the last quarter of 2022; and some 1.370,000 in the urban area; and the wider Copenhagen metropolitan ar ...
, where he met
Werner Heisenberg
Werner Karl Heisenberg () (5 December 1901 – 1 February 1976) was a German theoretical physicist and one of the main pioneers of the theory of quantum mechanics. He published his work in 1925 in a breakthrough paper. In the subsequent series ...
,
Hans Kramers
Hendrik Anthony "Hans" Kramers (17 December 1894 – 24 April 1952) was a Dutch physicist who worked with Niels Bohr to understand how electromagnetic waves interact with matter and made important contributions to quantum mechanics and statistical ...
,
Wolfgang Pauli
Wolfgang Ernst Pauli (; ; 25 April 1900 – 15 December 1958) was an Austrian theoretical physicist and one of the pioneers of quantum physics. In 1945, after having been nominated by Albert Einstein, Pauli received the Nobel Prize in Physics fo ...
,
Georg von Hevesy
George Charles de Hevesy (born György Bischitz; hu, Hevesy György Károly; german: Georg Karl von Hevesy; 1 August 1885 – 5 July 1966) was a Hungarian radiochemist and Nobel Prize in Chemistry laureate, recognized in 1943 for his key role ...
, and
John Slater. At the conclusion of his stay, he traveled to Germany, where he met
Albert Einstein
Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...
and
James Franck
James Franck (; 26 August 1882 – 21 May 1964) was a German physicist who won the 1925 Nobel Prize for Physics with Gustav Hertz "for their discovery of the laws governing the impact of an electron upon an atom". He completed his doctorate in ...
.
On returning to the United States, Urey received an offer of a
National Research Council National Research Council may refer to:
* National Research Council (Canada), sponsoring research and development
* National Research Council (Italy), scientific and technological research, Rome
* National Research Council (United States), part of ...
fellowship to
Harvard University
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...
, and also received an offer to be a research associate at
Johns Hopkins University
Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hem ...
. He chose the latter. Before taking up the job, he traveled to
Seattle, Washington
Seattle ( ) is a port, seaport city on the West Coast of the United States. It is the county seat, seat of King County, Washington, King County, Washington (state), Washington. With a 2020 population of 737,015, it is the largest city in bo ...
, to visit his mother. On the way, he stopped by
Everett, Washington
Everett is the county seat and largest city of Snohomish County, Washington, United States. It is north of Seattle and is one of the main cities in the metropolitan area and the Puget Sound region. Everett is the seventh-largest city in the ...
, where he knew Dr. Kate Daum, a colleague from the University of Montana. Dr. Daum introduced Urey to her sister, Frieda. Urey and Frieda soon became engaged. They were married at her father's house in
Lawrence, Kansas
Lawrence is the county seat of Douglas County, Kansas, Douglas County, Kansas, United States, and the sixth-largest city in the state. It is in the northeastern sector of the state, astride Interstate 70, between the Kansas River, Kansas and Waka ...
, in 1926. The couple had four children:
Gertrude Bessie (Elizabeth), born in 1927; Frieda Rebecca, born in 1929; Mary Alice, born in 1934; and John Clayton Urey, born in 1939.
At Johns Hopkins, Urey and
Arthur Ruark wrote ''Atoms, Quanta and Molecules'' (1930), one of the first English texts on quantum mechanics and its applications to atomic and molecular systems. In 1929, Urey became an associate professor of Chemistry at
Columbia University
Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhatt ...
, where his colleagues included
Rudolph Schoenheimer, David Rittenberg, and T. I. Taylor.
Deuterium
In the 1920s,
William Giauque
William Francis Giauque (;''The Columbia Electronic Encyclopedia'', 2004. May 12, 1895 – March 28, 1982) was a Canadian-born American chemist and Nobel laureate recognized in 1949 for his studies in the properties of matter at temperatures clo ...
and
Herrick L. Johnston discovered the stable
isotopes of oxygen
There are three known stable isotopes of oxygen (8O): , , and .
Radioactive isotopes ranging from to have also been characterized, all short-lived. The longest-lived radioisotope is with a half-life of , while the shortest-lived isotope is ...
. Isotopes were not well understood at the time;
James Chadwick
Sir James Chadwick, (20 October 1891 – 24 July 1974) was an English physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932. In 1941, he wrote the final draft of the MAUD Report, which inspi ...
would not discover the
neutron
The neutron is a subatomic particle, symbol or , which has a neutral (not positive or negative) charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons beh ...
until 1932. Two systems were in use for classifying them, based on chemical and physical properties. The latter was determined using the
mass spectrograph
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used ...
. Since it was known that the
atomic weight
Relative atomic mass (symbol: ''A''; sometimes abbreviated RAM or r.a.m.), also known by the deprecated synonym atomic weight, is a dimensionless physical quantity defined as the ratio of the average mass of atoms of a chemical element in a giv ...
of oxygen was almost exactly 16 times as heavy as hydrogen,
Raymond Birge, and
Donald Menzel
Donald Howard Menzel (April 11, 1901 – December 14, 1976) was one of the first theoretical astronomers and astrophysicists in the United States. He discovered the physical properties of the solar chromosphere, the chemistry of stars, the atmos ...
hypothesized that hydrogen had more than one isotope as well. Based upon the difference between the results of the two methods, they predicted that only one hydrogen atom in 4,500 was of the heavy isotope.
In 1931, Urey set out to find it. Urey and George M. Murphy (1903–1968) calculated from the
Balmer series
The Balmer series, or Balmer lines in atomic physics, is one of a set of six named series describing the spectral line emissions of the hydrogen atom. The Balmer series is calculated using the Balmer formula, an empirical equation discovered b ...
that the heavy isotope should have lines
blueshift
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in fr ...
ed (correspondingly the light isotope
redshift
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in f ...
ed) by . Urey had access to a
grating
A grating is any regularly spaced collection of essentially identical, parallel, elongated elements. Gratings usually consist of a single set of elongated elements, but can consist of two sets, in which case the second set is usually perpendicul ...
spectrograph
An optical spectrometer (spectrophotometer, spectrograph or spectroscope) is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify mate ...
, a sensitive device that had been recently installed at Columbia and was capable of resolving the Balmer series. With a resolution of 1 Å per millimetre, the machine should have produced a difference of about 1 millimetre. However, since only one atom in 4,500 was heavy, the line on the spectrograph was very faint. Urey therefore decided to delay publishing their results until he had more conclusive evidence that it was heavy hydrogen.
Urey and Murphy calculated from the
Debye model
In thermodynamics and solid-state physics, the Debye model is a method developed by Peter Debye in 1912 for estimating the phonon contribution to the specific heat (Heat capacity) in a solid. It treats the vibrations of the atomic lattice (hea ...
that the heavy isotope would have a slightly higher boiling point than the light one. By carefully warming liquid hydrogen, 5 litres of liquid hydrogen could be distilled to 1 millilitre, which would be enriched in the heavy isotope by 100 to 200 times. To obtain five litres of liquid hydrogen, they traveled to the cryogenics laboratory at the
National Bureau of Standards
The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical sci ...
in Washington, D.C., where they obtained the help of
Ferdinand Brickwedde, whom Urey had known at Johns Hopkins.
The first sample that Brickwedde sent was evaporated at at a pressure of . To their surprise, this showed no evidence of enrichment. Brickwedde then prepared a second sample evaporated at at a pressure of . On this sample, the Balmer lines for heavy hydrogen were seven times as intense.
The paper announcing the discovery of heavy hydrogen, later named
deuterium
Deuterium (or hydrogen-2, symbol or deuterium, also known as heavy hydrogen) is one of two Stable isotope ratio, stable isotopes of hydrogen (the other being Hydrogen atom, protium, or hydrogen-1). The atomic nucleus, nucleus of a deuterium ato ...
, was jointly published by Urey, Murphy, and Brickwedde in 1932. Urey was awarded the
Nobel Prize in Chemistry
)
, image = Nobel Prize.png
, alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then "M ...
in 1934 "for his discovery of heavy hydrogen". He declined to attend the ceremony in Stockholm, so that he could be present at the birth of his daughter Mary Alice.
Working with
Edward W. Washburn from the Bureau of Standards, Urey subsequently discovered the cause of the anomalous sample. Brickwedde's hydrogen had been separated from water by
electrolysis
In chemistry and manufacturing, electrolysis is a technique that uses direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction. Electrolysis is commercially important as a stage in the separation of elements from n ...
, resulting in a depleted sample. Moreover,
Francis William Aston
Francis William Aston Fellow of the Royal Society, FRS (1 September 1877 – 20 November 1945) was a British chemist and physicist who won the 1922 Nobel Prize in Chemistry for his discovery, by means of his mass spectrograph, of isotopes in man ...
had reported that his calculated value for the atomic weight of hydrogen was wrong, thereby invalidating Birge and Menzel's original reasoning. The discovery of deuterium stood, however.
Urey and Washburn attempted to use electrolysis to create pure
heavy water. Their technique was sound, but they were beaten to it in 1933 by Lewis, who had the resources of the University of California at his disposal. Using the
Born–Oppenheimer approximation
In quantum chemistry and molecular physics, the Born–Oppenheimer (BO) approximation is the best-known mathematical approximation in molecular dynamics. Specifically, it is the assumption that the wave functions of atomic nuclei and electro ...
, Urey and
David Rittenberg calculated the properties of gases containing hydrogen and deuterium. They extended this to enriching compounds of carbon, nitrogen, and oxygen. These could be used as tracers in
biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology and ...
, resulting in a whole new way of examining chemical reactions. He founded the
Journal of Chemical Physics
''The Journal of Chemical Physics'' is a scientific journal published by the American Institute of Physics that carries research papers on chemical physics.[Atlanticist
Atlanticism, also known as Transatlanticism, is the belief in or support for a close relationship between the peoples and governments in Northern America (the United States and Canada) and those in Europe (the countries of the European Union, the ...]
Clarence Streit
Clarence Kirschman Streit (; January 21, 1896 – July 6, 1986) was an American journalist who played a prominent role in the Atlanticist and world federalist movements.Imlay, Talbot (2020)Streit, Federalist Frameworks, and Wartime American Inte ...
's proposal for a federal union of the world's major
democracies
Democracy (From grc, δημοκρατία, dēmokratía, ''dēmos'' 'people' and ''kratos'' 'rule') is a form of government in which the people have the authority to deliberate and decide legislation (" direct democracy"), or to choose gov ...
, and the
republican
Republican can refer to:
Political ideology
* An advocate of a republic, a type of government that is not a monarchy or dictatorship, and is usually associated with the rule of law.
** Republicanism, the ideology in support of republics or agains ...
cause during the
Spanish Civil War
The Spanish Civil War ( es, Guerra Civil Española)) or The Revolution ( es, La Revolución, link=no) among Nationalists, the Fourth Carlist War ( es, Cuarta Guerra Carlista, link=no) among Carlists, and The Rebellion ( es, La Rebelión, lin ...
. He was an early opponent of German
Nazism
Nazism ( ; german: Nazismus), the common name in English for National Socialism (german: Nationalsozialismus, ), is the far-right totalitarian political ideology and practices associated with Adolf Hitler and the Nazi Party (NSDAP) in Na ...
and assisted refugee scientists, including
Enrico Fermi
Enrico Fermi (; 29 September 1901 – 28 November 1954) was an Italian (later naturalized American) physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1. He has been called the "architect of the nuclear age" and ...
, by helping them find work in the United States, and to adjust to life in a new country.
Manhattan Project
By the time World War II broke out in Europe in 1939, Urey was recognized as a world expert on isotope separation. Thus far, separation had involved only the light elements. In 1939 and 1940, Urey published two papers on the separation of heavier isotopes in which he proposed centrifugal separation. This assumed great importance due to speculation by Niels Bohr that
uranium 235
Uranium-235 (235U or U-235) is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope uranium-238, it is fissile, i.e., it can sustain a nuclear chain reaction. It is the only fissile isotope that exists ...
was
fissile
In nuclear engineering, fissile material is material capable of sustaining a nuclear fission chain reaction. By definition, fissile material can sustain a chain reaction with neutrons of thermal energy. The predominant neutron energy may be typ ...
. Because it was considered "very doubtful whether a chain reaction can be established without separating 235 from the rest of the uranium," Urey began intensive studies of how uranium enrichment might be achieved. Apart from centrifugal separation,
George Kistiakowsky
George may refer to:
People
* George (given name)
* George (surname)
* George (singer), American-Canadian singer George Nozuka, known by the mononym George
* George Washington, First President of the United States
* George W. Bush, 43rd President ...
suggested that
gaseous diffusion
Gaseous diffusion is a technology used to produce enriched uranium by forcing gaseous uranium hexafluoride (UF6) through semipermeable membranes. This produces a slight separation between the molecules containing uranium-235 (235U) and uranium-2 ...
might be a possible method. A third possibility was
thermal diffusion. Urey coordinated all isotope separation research efforts, including the effort to produce heavy water, which could be used as a
neutron moderator
In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, ideally without capturing any, leaving them as thermal neutrons with only minimal (thermal) kinetic energy. These thermal neutrons are immensely mo ...
in
nuclear reactor
A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nu ...
s.
![S1 Committee 1942](https://upload.wikimedia.org/wikipedia/commons/e/ef/S1_Committee_1942.jpg)
In May 1941, Urey was appointed to the
Committee on Uranium, which oversaw the uranium project as part of the
National Defense Research Committee
The National Defense Research Committee (NDRC) was an organization created "to coordinate, supervise, and conduct scientific research on the problems underlying the development, production, and use of mechanisms and devices of warfare" in the Un ...
(NDRC). In 1941, Urey and
George B. Pegram
George Braxton Pegram (October 24, 1876 – August 12, 1958) was an American physicist who played a key role in the technical administration of the Manhattan Project. He graduated from Trinity College (now Duke University) in 1895, and taught high ...
led a diplomatic mission to England to establish co-operation on development of the atomic bomb. The British were optimistic about gaseous diffusion, but it was clear that both gaseous and centrifugal methods faced formidable technical obstacles. In May 1943, as the
Manhattan Project
The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project w ...
gained momentum. Urey became head of the wartime Substitute Alloy Materials Laboratories (
SAM Laboratories
K-25 was the codename given by the Manhattan Project to the program to produce enriched uranium for atomic bombs using the gaseous diffusion method. Originally the codename for the product, over time it came to refer to the project, the produ ...
) at Columbia, which was responsible for the heavy water and all the isotope enrichment processes except
Ernest Lawrence
Ernest Orlando Lawrence (August 8, 1901 – August 27, 1958) was an American nuclear physicist and winner of the Nobel Prize in Physics in 1939 for his invention of the cyclotron. He is known for his work on uranium-isotope separation f ...
's electromagnetic process.
Early reports on the centrifugal method indicated that it was not as efficient as predicted. Urey suggested that a more efficient but technically more complicated countercurrent system be used instead of the previous flow-through method. By November 1941, technical obstacles seemed formidable enough for the process to be abandoned. Countercurrent centrifuges were developed after the war, and today are the favored method in many countries.
The gaseous diffusion process remained more encouraging, although it too had technical obstacles to overcome. By the end of 1943, Urey had over 700 people working for him on gaseous diffusion. The process involved hundreds of cascades, in which corrosive
uranium hexafluoride
Uranium hexafluoride (), (sometimes called "hex") is an inorganic compound with the formula UF6. Uranium hexafluoride is a volatile white solid that reacts with water, releasing corrosive hydrofluoric acid. The compound reacts mildly with alumin ...
diffused through gaseous barriers, becoming progressively more enriched at every stage. A major problem was finding proper seals for the pumps, but by far the greatest difficulty lay in constructing an appropriate diffusion barrier. Construction of the huge
K-25
K-25 was the codename given by the Manhattan Project to the program to produce enriched uranium for atomic bombs using the gaseous diffusion method. Originally the codename for the product, over time it came to refer to the project, the prod ...
gaseous diffusion plant was well under way before a suitable barrier became available in quantity in 1944. As a backup, Urey championed thermal diffusion.
Worn out by the effort, Urey left the project in February 1945, handing over his responsibilities to R. H. Crist. The K-25 plant commenced operation in March 1945, and as the bugs were worked out, the plant operated with remarkable efficiency and economy. For a time, uranium was fed into the
S50 liquid thermal diffusion plant, then the K-25 gaseous, and finally the
Y-12 electromagnetic separation plant; but soon after the war ended the thermal and electromagnetic separation plants were closed down, and separation was performed by K-25 alone. Along with its twin, K-27, constructed in 1946, it became the principal isotope separation plant in the early post-war period. For his work on the Manhattan Project, Urey was awarded the
Medal for Merit
The Medal for Merit was, during the period it was awarded, the highest civilian decoration of the United States. It was awarded by the President of the United States to civilians who "distinguished themselves by exceptionally meritorious conduct i ...
by the Project director,
Major General
Major general (abbreviated MG, maj. gen. and similar) is a military rank used in many countries. It is derived from the older rank of sergeant major general. The disappearance of the "sergeant" in the title explains the apparent confusion of a ...
Leslie R. Groves, Jr.
Lieutenant General Leslie Richard Groves Jr. (17 August 1896 – 13 July 1970) was a United States Army Corps of Engineers officer who oversaw the construction of the Pentagon and directed the Manhattan Project, a top secret research project ...
Post-war years
After the war, Urey became professor of chemistry at the
Institute for Nuclear Studies
__NOTOC__
The Institute for Nuclear Studies was founded September 1945 as part of the University of Chicago with Samuel King Allison as director. On November 20, 1955, it was renamed The Enrico Fermi Institute for Nuclear Studies. The name was sh ...
, and then became Ryerson professor of chemistry at the
University of Chicago
The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...
in 1952.
He did not continue his pre-war research with isotopes. However, applying the knowledge gained with hydrogen to oxygen, he realized that the
fractionation
Fractionation is a separation process in which a certain quantity of a mixture (of gases, solids, liquids, enzymes, or isotopes, or a suspension) is divided during a phase transition, into a number of smaller quantities (fractions) in which the ...
between
carbonate
A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonate g ...
and water for
oxygen-18
Oxygen-18 (, Ω) is a natural, stable isotope of oxygen and one of the environmental isotopes.
is an important precursor for the production of fluorodeoxyglucose (FDG) used in positron emission tomography (PET). Generally, in the radiopharmaceu ...
and
oxygen-16
Oxygen-16 (16O) is a stable isotope of oxygen, having 8 neutrons and 8 protons in its nucleus. It has a mass of . Oxygen-16 is the most abundant isotope of oxygen and accounts for 99.762% of oxygen's natural abundance. The relative and absolute ...
would decrease by a factor of 1.04 between . The ratio of the isotopes could then be used to determine average temperatures, assuming that the measurement equipment was sufficiently sensitive. The team included his colleague
Ralph Buchsbaum. Examination of a 100-million-year-old
belemnite
Belemnitida (or the belemnite) is an extinct order of squid-like cephalopods that existed from the Late Triassic to Late Cretaceous. Unlike squid, belemnites had an internal skeleton that made up the cone. The parts are, from the arms-most to ...
then indicated the summer and winter temperatures that it had lived through over a period of four years. For this pioneering
paleoclimatic
Paleoclimatology (British spelling, palaeoclimatology) is the study of climates for which direct measurements were not taken. As instrumental records only span a tiny part of Earth's history, the reconstruction of ancient climate is important to ...
research, Urey was awarded the
Arthur L. Day Medal by the
Geological Society of America
The Geological Society of America (GSA) is a nonprofit organization dedicated to the advancement of the geosciences.
History
The society was founded in Ithaca, New York, in 1888 by Alexander Winchell, John J. Stevenson, Charles H. Hitchco ...
, and the Goldschmidt Medal of the
Geochemical Society
The Geochemical Society is a nonprofit scientific organization founded to encourage the application of chemistry to solve problems involving geology and cosmology. The society promotes understanding of geochemistry through the annual Goldschmidt Co ...
. While at the University of Chicago, Urey contributed to the
Urey-Bigeleisen-Mayer equation
In stable isotope geochemistry, the Urey-Bigeleisen-Mayer equation, also known as the Bigeleisen-Mayer equation or the Urey model, is a model describing the approximate equilibrium isotope fractionation in an isotope exchange reaction. While the e ...
, a model of stable isotope fractionation.
![Miller-Urey experiment-en](https://upload.wikimedia.org/wikipedia/commons/5/54/Miller-Urey_experiment-en.svg)
Urey actively campaigned against the 1946
May-Johnson bill because he feared that it would lead to military control of nuclear energy, but supported and fought for the McMahon bill that replaced it, and ultimately created the
Atomic Energy Commission. Urey's commitment to the ideal of
world government
World government is the concept of a single political authority with jurisdiction over all humanity. It is conceived in a variety of forms, from tyrannical to democratic, which reflects its wide array of proponents and detractors.
A world gove ...
dated from before the war, but the possibility of
nuclear war
Nuclear warfare, also known as atomic warfare, is a theoretical military conflict or prepared political strategy that deploys nuclear weaponry. Nuclear weapons are weapons of mass destruction; in contrast to conventional warfare, nuclear w ...
made it only more urgent in his mind. He went on lecture tours against war, and became involved in Congressional debates regarding nuclear issues. He argued publicly on behalf of
Ethel and Julius Rosenberg
Julius Rosenberg (May 12, 1918 – June 19, 1953) and Ethel Rosenberg (; September 28, 1915 – June 19, 1953) were American citizens who were convicted of spying on behalf of the Soviet Union. The couple were convicted of providing top-secret i ...
, and was called before the
House Un-American Activities Committee
The House Committee on Un-American Activities (HCUA), popularly dubbed the House Un-American Activities Committee (HUAC), was an investigative committee of the United States House of Representatives, created in 1938 to investigate alleged disloy ...
.
Cosmochemistry and the Miller–Urey experiment
In later life, Urey helped develop the field of
cosmochemistry
Cosmochemistry (from Greek κόσμος ''kósmos'', "universe" and χημεία ''khemeía'') or chemical cosmology is the study of the chemical composition of matter in the universe and the processes that led to those compositions. This is done ...
and is credited with coining the term. His work on oxygen-18 led him to develop theories about the
abundance of the chemical elements
The abundance of the chemical elements is a measure of the Type–token distinction#Occurrences, occurrence of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by the mass frac ...
on earth, and of their abundance and evolution in the stars. Urey summarized his work in ''The Planets: Their Origin and Development'' (1952). Urey speculated that the early terrestrial
atmosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...
was composed of
ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...
,
methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Eart ...
, and hydrogen. One of his Chicago graduate students,
Stanley L. Miller, showed in the ''
Miller–Urey experiment
The Miller–Urey experiment (or Miller experiment) is a famous chemistry experiment that simulated the conditions thought at the time (1952) to be present in the atmosphere of the early, prebiotic Earth, in order to test the hypothesis of the ...
'' that, if such a mixture is exposed to electric sparks and to water, it can interact to produce
amino acids
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...
, commonly considered the building blocks of life.
Urey spent a year in the United Kingdom as a visiting professor at
Oxford University
Oxford () is a city in England. It is the county town and only city of Oxfordshire. In 2020, its population was estimated at 151,584. It is north-west of London, south-east of Birmingham and north-east of Bristol. The city is home to the ...
in 1956 and 1957.
In 1958, he reached the University of Chicago's retirement age of 65, but he accepted a post as a professor at large at the new
University of California, San Diego
The University of California, San Diego (UC San Diego or colloquially, UCSD) is a public university, public Land-grant university, land-grant research university in San Diego, California. Established in 1960 near the pre-existing Scripps Insti ...
(UCSD), and moved to
La Jolla, California
La Jolla ( , ) is a hilly, seaside neighborhood within the city of San Diego, California, United States, occupying of curving coastline along the Pacific Ocean. The population reported in the 2010 census was 46,781.
La Jolla is surrounded on ...
. He was subsequently made a
professor emeritus
''Emeritus'' (; female: ''emerita'') is an adjective used to designate a retired chair, professor, pastor, bishop, pope, director, president, prime minister, rabbi, emperor, or other person who has been "permitted to retain as an honorary title ...
there from 1970 to 1981.
Urey helped build up the science faculty there. He was one of the founding members of UCSD's school of chemistry, which was created in 1960, along with Stanley Miller,
Hans Suess
Hans Eduard Suess (December 16, 1909 – September 20, 1993) was an Austrian born United States, American physical chemist and nuclear physicist. He was a grandson of the Austrian geologist Eduard Suess.
Career
Suess earned his Ph.D. in chemist ...
, and
Jim Arnold.
In the late 1950s and early 1960s, space science became a topic of research in the wake of the launch of
Sputnik I
Sputnik 1 (; see § Etymology) was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space program. It sent a radio signal back to Earth for t ...
. Urey helped persuade
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
to make unmanned probes to the moon a priority. When
Apollo 11
Apollo 11 (July 16–24, 1969) was the American spaceflight that first landed humans on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin landed the Apollo Lunar Module ''Eagle'' on July 20, 1969, at 20:17 UTC, an ...
returned
moon rock
Moon rock or lunar rock is rock originating from Earth's Moon. This includes lunar material collected during the course of human exploration of the Moon, and rock that has been ejected naturally from the Moon's surface and landed on Earth as ...
samples from the moon, Urey examined them at the
Lunar Receiving Laboratory
The Lunar Receiving Laboratory (LRL) was a facility at NASA's Lyndon B. Johnson Space Center (Building 37) that was constructed to quarantine astronauts and material brought back from the Moon during the Apollo program to reduce the risk of ...
. The samples supported Urey's contention that the moon and the Earth shared a common origin. While at UCSD, Urey published 105 scientific papers, 47 of them about lunar topics. When asked why he continued to work so hard, he joked, "Well, you know I'm not on tenure anymore."
Death and legacy
Urey enjoyed gardening and raising
cattleya
''Cattleya'' () is a genus of orchids from Costa Rica south to Argentina. The genus is abbreviated C in trade journals.
Description
Epiphytic or terrestrial orchids with cylindrical rhizome from which the fleshy noodle-like roots grow. Pseu ...
,
cymbidium
''Cymbidium'' , commonly known as boat orchids, is a genus of evergreen flowering plants in the orchid family Orchidaceae. Orchids in this genus are epiphytic, lithophytic, terrestrial or rarely leafless saprophytic herbs usually with pseudobulbs ...
and other
orchids
Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant.
Along with the Asteraceae, they are one of the two largest families of flowering ...
. He died at La Jolla, California, and is buried in the Fairfield Cemetery in
DeKalb County, Indiana
DeKalb County is a county in the U.S. state of Indiana. As of the 2020 United States Census, the population was 43,265. The county seat is Auburn.
History
On 7 February 1835, the Indiana State Legislature passed an omnibus bill that authorized t ...
.
Apart from his Nobel Prize, he also won the
Franklin Medal
The Franklin Medal was a science award presented from 1915 until 1997 by the Franklin Institute located in Philadelphia, Pennsylvania, U.S. It was founded in 1914 by Samuel Insull
Samuel Insull (November 11, 1859 – July 16, 1938) was a Bri ...
in 1943, the
J. Lawrence Smith Medal
J. Lawrence Smith Medal is awarded every three years by the National Academy of Sciences for investigations of meteoric bodies. The medal is in honor of its namesake, the American chemist and meteoriticist, J. Lawrence Smith.
Recipients
Sour ...
in 1962, the
Gold Medal of the Royal Astronomical Society
The Gold Medal of the Royal Astronomical Society is the highest award given by the Royal Astronomical Society (RAS). The RAS Council have "complete freedom as to the grounds on which it is awarded" and it can be awarded for any reason. Past awar ...
in 1966, the Golden Plate Award of the
American Academy of Achievement
The American Academy of Achievement, colloquially known as the Academy of Achievement, is a non-profit educational organization that recognizes some of the highest achieving individuals in diverse fields and gives them the opportunity to meet o ...
in 1966, and the
Priestley Medal
The Priestley Medal is the highest honor conferred by the American Chemical Society (ACS) and is awarded for distinguished service in the field of chemistry. Established in 1922, the award is named after Joseph Priestley, the discoverer of oxygen ...
of the
American Chemical Society
The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all d ...
in 1973. In 1964 he received the
National Medal of Science
The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social scienc ...
. He became a
Fellow of the Royal Society
Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural science, natural knowledge, incl ...
in 1947.
Named after him are
lunar
Lunar most commonly means "of or relating to the Moon".
Lunar may also refer to:
Arts and entertainment
* ''Lunar'' (series), a series of video games
* "Lunar" (song), by David Guetta
* "Lunar", a song by Priestess from the 2009 album ''Prior t ...
impact crater
An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters ...
Urey,
asteroid
4716 Urey, and the
H. C. Urey Prize, awarded for achievement in
planetary science
Planetary science (or more rarely, planetology) is the scientific study of planets (including Earth), celestial bodies (such as moons, asteroids, comets) and planetary systems (in particular those of the Solar System) and the processes of their f ...
s by the
American Astronomical Society
The American Astronomical Society (AAS, sometimes spoken as "double-A-S") is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC. The primary objective of the AAS is to promote the adv ...
. The Harold C. Urey Middle School in Walkerton, Indiana, is also named for him, as is Urey Hall, the chemistry building at Revelle College, UCSD, in La Jolla and the Harold C. Urey Lecture Hall at the University of Montana. UCSD has also established a Harold C. Urey chair whose first holder is James Arnold.
Urey's daughter,
Elizabeth Baranger, also became a notable physicist.
See also
*
Carbonate–silicate cycle
The carbonate–silicate geochemical cycle, also known as the inorganic carbon cycle, describes the long-term transformation of silicate rocks to Carbonate rock, carbonate rocks by weathering and sedimentation, and the transformation of carbonate ...
Notes
References
* Urey, H. C. (1952)
The planets: Their origin and development.Mrs. Hepsa Ely Silliman Memorial Lectures. Document in which Urey describes the
carbonate–silicate geochemical cycle controlling the long-term climate on Earth during the geological ages (see Berner, Lasaga and Garrels (1983) on the subject).
*
*
*
*
*
External links
Harold Clayton Urey PapersMSS 44
Special Collections & Archives UC San Diego Library.
1965 Audio Interview with Harold Urey by Stephane GroueffVoices of the Manhattan Project
Harold Urey – Explaining why he rejects the notion of the moon breaking away from the earth – 1972* including the Nobel Lecture on February 14, 1935 ''Some Thermodynamic Properties of Hydrogen and Deuterium''
Guide to the Harold C. Urey Papers 1932-1953at th
University of Chicago Special Collections Research Center
{{DEFAULTSORT:Urey, Harold C.
1893 births
1981 deaths
People from Leonia, New Jersey
People from St. Joseph County, Indiana
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Nobel laureates in Chemistry
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Columbia University faculty
UC Berkeley College of Chemistry alumni
University of Chicago faculty
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Mass spectrometrists
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