Harold Urey, circa 1963.

Harold Clayton Urey (April 29, 1893 – January 5, 1981) was a chemist whose pioneering work on isotopes earned him the Nobel Prize in Chemistry in 1934 and later led him to theories of planetary evolution. Harold C. Urey From [history. ... Harold C. Urey From [history. ... April 29 is the 119th day of the year in the Gregorian calendar (120th in leap years). ... 1893 was a common year starting on Sunday (see link for calendar). ... January 5 is the 5th day of the year in the Gregorian Calendar. ... 1981 (MCMLXXXI) is a common year starting on Thursday of the Gregorian calendar. ... Look up chemist on Wiktionary, the free dictionary. ... Isotopes are forms of an element whose nuclei have the same atomic number–-the number of protons in the nucleus--but different atomic masses because they contain different numbers of neutrons. ... List of Nobel Prize laureates in Chemistry from 1901 to the present day. ... 1934 (MCMXXXIV) was a common year starting on Monday (link will take you to calendar). ...

Biography

Urey was born in Walkerton, Indiana. After briefly teaching in rural schools, Urey earned a degree in zoology from the University of Montana and a Ph.D. in chemistry, studying thermodynamics under Gilbert N. Lewis at the University of California, Berkeley. Walkerton is a town located in St. ... Zoology (Greek zoon = animal and logos = word) is the biological discipline which involves the study of animals. ... University of Montana The University of Montana campus, 1999. ... Thermodynamics (from the Greek thermos meaning heat and dynamis meaning power) is a branch of physics that studies the effects of temperature on physical systems at the macroscopic scale. ... Lewis in the Berkeley Lab Gilbert Newton Lewis (October 23, 1875-March 23, 1946) was a famous American physical chemist. ... University of California, Berkeley The University of California, Berkeley (also known as Cal, UCB, UC Berkeley, The University of California, California, or simply Berkeley) is a public coeducational university situated east of the San Francisco Bay in Berkeley, California, overlooking the Golden Gate. ...

At Berkeley, Urey was influenced by the work of physicist Raymond T. Birge and soon joined Niels Bohr in Copenhagen to work on atomic structure at the Institute for Theoretical Physics. On his return to the US in 1924 he taught at Johns Hopkins University, and then at Columbia where he assembled a team of associates that included Rudolph Schoenheimer, David Rittenberg and T. I. Taylor. A physicist is a scientist trained in physics. ... Raymond Thayer Birge (March 13, 1887 - March 22, 1980) was a physicist. ... Niels Bohr Niels Henrik David Bohr (October 7, 1885 – November 18, 1962) was a Danish physicist who made essential contributions to understanding atomic structure and quantum mechanics. ... Copenhagen (Danish: København) is the capital and largest city of Denmark, and the name of the municipality (Danish, kommune) in which it resides. ... The Niels Bohr Institute is part of the Niels Bohr Institute for Astronomy, Physics and Geophysics of the University of Copenhagen. ... Wikiquote has a collection of quotations by or about: United States Wikinews has news related to this article: United States United States government CIA World Factbook Entry for United States House. ... 1924 was a leap year starting on Tuesday (link will take you to calendar). ... The Johns Hopkins University is a private institution of higher learning located in Baltimore, Maryland. ... Rudolph Schoenheimer (May 10, 1898, - September 11, 1941) was a German/ US biochemist who developed the technique of radioactive tagging of molecules, enabling detailed study of metabolism. ... David Rittenberg (November 11, 1906 — January 24, 1970) was a US biochemist who pioneered the radioactive tagging of molecules enabling detailed studies of metabolism. ... This article lacks information on the importance of the subject matter. ...

During this time, Urey isolated deuterium by repeatedly distilling a sample of liquid hydrogen. In 1931, he and his associates went on to demonstrate the existence of heavy water. Urey was awarded the Nobel Prize in Chemistry in 1934 for this work. Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance of one atom in 6500 of hydrogen. ... Distillation is a means of separating liquids through differences in their boiling points. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... 1931 is a common year starting on Thursday. ... Heavy water is dideuterium oxide, or D2O or 2H2O. It is chemically the same as normal water, H2O, but the hydrogen atoms are of the heavy isotope deuterium, in which the nucleus contains a neutron in addition to the proton found in the nucleus of any hydrogen atom. ... List of Nobel Prize laureates in Chemistry from 1901 to the present day. ... 1934 (MCMXXXIV) was a common year starting on Monday (link will take you to calendar). ...

During World War II, Urey's team at Columbia worked on a number of research programs that contributed towards the Manhattan Project to develop an atomic bomb for the United States. Most importantly, they developed the gaseous diffusion method to separate uranium-235 from uranium-238. In autumn 1941, Urey, with G. B. Pegram, led a diplomatic mission to England to establishing co-operation on development of the atomic bomb. World War II was a truly global conflict with many facets: immense human suffering, fierce indoctrinations, and the use of new, extremely devastating weapons such as the atom bomb. ... Control panels and operators for calutrons at the Y-12 Plant in Oak Ridge, Tennessee. ... The mushroom cloud of the atomic bombing of Nagasaki, Japan, 1945, rose some 18 km (11 mi) above the epicenter. ... Isotope separation is the process of concentrating specific isotopes of a chemical element by removing other isotopes. ... Uranium-235 is an isotope of uranium that differs from the elements other common isotope, uranium-238, by its ability to cause a rapidly expanding fission chain reaction. ... There are two objects with this name: Unterseeboot 238 Uranium-238, the most common isotope of uranium This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... 1941 was a common year starting on Wednesday (link will take you to calendar). ... George Braxton Pegram (October 24, 1876 - August 12, 1958) was a US physicist who played a key role in the technical administration of the Manhattan Project. ... Royal motto (French): Dieu et mon droit (Translated: God and my right) Englands location within the UK Official language English de facto Capital London de facto Largest city London Area - Total Ranked 1st UK 130,395 km² Population - Total (mid-2004) - Density Ranked 1st UK 50. ...

After the war, he became professor of chemistry at the Institute for Nuclear Studies, then Ryerson professor of chemistry at the University of Chicago before progressing to honorific offices at the University of California, San Diego. The Institute for Nuclear Studies was founded September, 1945 as part of the University of Chicago with Samuel King Allison as director. ... The University of Chicago is a private co-educational university located in Chicago, Illinois. ... The University of California, San Diego (popularly known as UCSD) is a public, coeducational university located in La Jolla, California. ...

In later life, Urey helped develop the field of cosmochemistry and is credited with coining the term. His work on oxygen-18 led him to develop theories about the abundance of the chemical elements on earth and of their abundance and evolution in the stars. Urey summarised his work in the book The Planets: Their Origin and Development (1952). Urey speculated that the early terrestrial atmosphere was probably composed of ammonia, methane and hydrogen; it was one of his Chicago graduate students, Stanley L. Miller, who showed that, if such a mixture be exposed to ultraviolet radiation and to water, it can interact to produce amino acids, the building blocks of life (see Miller-Urey experiment). However, many modern scientists now believe that the Earth's early atmosphere consisted mostly of carbon dioxide and water vapor. Cosmochemistry is concerned with the origin and development of the elements and their isotopes in the universe. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... The abundance of a chemical element measures how common the element is, or how much of the element there is. ... The abundance of a chemical element measures how common the element is, or how much of the element there is. ... 1952 was a leap year starting on Tuesday (link will take you to calendar). ... Layers of Atmosphere (NOAA) The Earths atmosphere is a layer of gases surrounding the planet Earth and retained by the Earths gravity. ... Ammonia is a compound of nitrogen and hydrogen with the formula NH3. ... R-phrases S-phrases , , , Flash point −188 °C Autoignition temperature 537 °C Explosive limits 5–15% Supplementary data page Structure and properties n, εr, etc. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... Stanley L. Miller (born 1930) is an American chemist famous for his role in the Miller-Urey experiment he performed in 1953, while a graduate student. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... In chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. ... The Miller-Urey experiment attempts to recreate the chemical conditions of the primitive Earth in the laboratory, and synthesized some of the building blocks of life. ...

Urey died at La Jolla, California, and is buried in the Fairfield Cemetery in DeKalb County, Indiana. One of the beaches at La Jolla Cove. ... DeKalb County is a county located in the state of Indiana. ...

Apart from his Nobel Prize, he also won the Gold Medal of the Royal Astronomical Society in 1966. Named after him are lunar impact crater Urey, asteroid 4716 Urey and the H. C. Urey Prize, awarded for achievement in planetary sciences by the American Astronomical Society. The Gold Medal is the highest award of the Royal Astronomical Society. ... 1966 was a common year starting on Saturday (link goes to calendar) // Events January January 1 - In a coup, Colonel Jean-Bédel Bokassa ousts president David Dacko and takes over the Central African Republic. ... Crust composition Oxygen 43% Silicon 21% Aluminium 10% Calcium 9% Iron 9% Magnesium 5% Titanium 2% Nickel 0. ... This article is about impact craters, also known as meteor craters. ... A portion of crater Urey and surroundings. ... The Harold C. Urey Prize is awarded annually by the Division for Planetary Sciences of the American Astronomical Society. ... Planetary science, also known as planetology or planetary astronomy, is the science of planets and the solar system, and incorporates an interdisciplinary approach drawing from diverse sciences. ... The American Astronomical Society (AAS) is a US society of professional astronomers and other interested individuals, headquartered in Washington, DC. The main aim of the AAS is provide a political voice for its members and organise their lobbying. ...

External links

• National Academy of Sciences biography
• his discovery of heavy hydrogen