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Gerald J. Wasserburg
Gerald J. Wasserburg (March 25, 1927 – June 13, 2016) was an American geologist. At the time of his death, he was the John D. MacArthur Professor of Geology and Geophysics, Emeritus, at the California Institute of Technology. He was known for his work in the fields of isotope geochemistry, cosmochemistry, meteoritics, and astrophysics. After leaving the US army, where he received the Combat Infantryman Badge, he graduated from high school and attended college on the G.I. Bill. Wasserburg completed his Ph.D. from the University of Chicago in 1954, with a thesis on the development of K–Ar dating, done under the sponsorship of Prof. H. C. Urey and Prof M. G. Inghram. He joined the faculty at Caltech in 1955 as Assistant Professor. He became Associate Professor in 1959 and Professor of Geology and Geophysics in 1962. In 1982 he became the John D. MacArthur Professor of Geology and Geophysics; he retired in 2001. He, Typhoon Lee and D.A. Papanastassiou discovered the presenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Brunswick, New Jersey
New Brunswick is a city (New Jersey), city in and the county seat, seat of government of Middlesex County, New Jersey, Middlesex County, in the U.S. state of New Jersey.New Jersey County Map New Jersey Department of State. Accessed July 10, 2017. The city is the home of Rutgers University. The city is both a regional commercial hub for Central Jersey, central New Jersey and a prominent and growing commuter town for residents commuting to New York City within the New York metropolitan area. New Brunswick is on the Northeast Corridor, Northeast Corridor rail line, southwest of Manhattan. The city is located on the southern banks of the Raritan River in the Raritan Valley region. For 2020 United States census, 2020, New Brunswick had a population of 55,266 residents, [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotope Geochemistry
Isotope geochemistry is an aspect of geology based upon the study of natural variations in the relative abundances of isotopes of various elements. Variations in isotopic abundance are measured by isotope ratio mass spectrometry, and can reveal information about the ages and origins of rock, air or water bodies, or processes of mixing between them. Stable isotope geochemistry is largely concerned with isotopic variations arising from mass-dependent isotope fractionation, whereas radiogenic isotope geochemistry is concerned with the products of natural radioactivity. Stable isotope geochemistry For most stable isotopes, the magnitude of fractionation from kinetic and equilibrium fractionation is very small; for this reason, enrichments are typically reported in "per mil" (‰, parts per thousand). These enrichments (δ) represent the ratio of heavy isotope to light isotope in the sample over the ratio of a standard. That is, :\delta \ce = \left( \frac -1 \right) \times 1000 â ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Werner Gast
Paul Werner Gast (September 11, 1930 – May 16, 1973) was an American geochemist and geologist. He was born in Chicago to German immigrants and attended Wheaton College, Illinois, whence he graduated in 1952. He earned a Ph.D. from Columbia University in 1957. After graduation, he taught at the University of Minnesota until 1965 when he became professor of geology at Columbia. In 1969 Paul Gast assumed leadership of the geo-science management of the Manned Spacecraft Center in preparation for Apollo mission sample return from the Moon. He served as chief scientist of the Apollo Lunar Science Staff. He was one of the science consultant group known unofficially as the "Four Horsemen," along with Jim Arnold, Bob Walker and Gerry Wasserburg. He died at the age of 43, being survived by his wife, Joyce Rinehart, and two sons and a daughter. During his career he pioneered the study of rare earth elements in examining the crust, mantle, and interior of the planet. He led the develo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James R
James is a common English language surname and given name: *James (name), the typically masculine first name James * James (surname), various people with the last name James James or James City may also refer to: People * King James (other), various kings named James * Saint James (other) * James (musician) * James, brother of Jesus Places Canada * James Bay, a large body of water * James, Ontario United Kingdom * James College, a college of the University of York United States * James, Georgia, an unincorporated community * James, Iowa, an unincorporated community * James City, North Carolina * James City County, Virginia ** James City (Virginia Company) ** James City Shire * James City, Pennsylvania * St. James City, Florida Arts, entertainment, and media * ''James'' (2005 film), a Bollywood film * ''James'' (2008 film), an Irish short film * ''James'' (2022 film), an Indian Kannada-language film * James the Red Engine, a character in ''Thomas the Tank En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Four Horsemen (NASA)
The Four Horsemen of the Apocalypse are figures in the Christian scriptures, first appearing in the Book of Revelation, a piece of apocalypse literature written by John of Patmos. Revelation 6 tells of a book or scroll in God's right hand that is sealed with seven seals. The Lamb of God/Lion of Judah opens the first four of the seven seals, which summons four beings that ride out on white, red, black, and pale horses. In John's revelation the first horseman rides a white horse, carries a bow, and is given a crown as a figure of conquest, perhaps invoking pestilence, Christ, or the Antichrist. The second carries a sword and rides a red horse as the creator of (civil) war, conflict, and strife. The third, a food merchant, rides a black horse symbolizing famine and carries the scales. The fourth and final horse is pale, upon it rides Death, accompanied by Hades. "They were given authority over a quarter of the earth, to kill with sword, famine and plague, and by means of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 back-contamination. After recovery at sea, crews from Apollo 11, Apollo 12, and Apollo 14 walked from their helicopter to the Mobile Quarantine Facility on the deck of an aircraft carrier and were brought to the LRL for quarantine. Samples of rock and regolith that the astronauts collected and brought back were flown directly to the LRL and initially analyzed in glovebox vacuum chambers. ::: The quarantine requirement was dropped for Apollo 15 and later missions. The LRL was used for study, distribution, and safe storage of the lunar samples. Between 1969 and 1972, six Apollo space flight missions brought back 382 kilograms (842 pounds) of lunar rocks, core samples, pebbles, sand, and dust from the lunar surface—in all, 2,200 sample ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Palladium
Naturally occurring palladium (46Pd) is composed of six stable isotopes, 102Pd, 104Pd, 105Pd, 106Pd, 108Pd, and 110Pd, although 102Pd and 110Pd are theoretically unstable. The most stable radioisotopes are 107Pd with a half-life of 6.5 million years, 103Pd with a half-life of 17 days, and 100Pd with a half-life of 3.63 days. Twenty-three other radioisotopes have been characterized with atomic weights ranging from 90.949 u (91Pd) to 128.96 u (129Pd). Most of these have half-lives that are less than a half an hour except 101Pd (half-life: 8.47 hours), 109Pd (half-life: 13.7 hours), and 112Pd (half-life: 21 hours). The primary decay mode before the most abundant stable isotope, 106Pd, is electron capture and the primary mode after is beta decay. The primary decay product before 106Pd is rhodium and the primary product after is silver. Radiogenic 107Ag is a decay product of 107Pd and was first discovered in the Santa Clara meteorite of 1978. The discoverers suggest that the coales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Aluminium
Aluminium or ''aluminum'' (13Al) has 22 known isotopes from 22Al to 43Al and 4 known isomers. Only 27Al (stable isotope) and 26Al (radioactive isotope, t1/2 = ) occur naturally, however 27Al comprises nearly all natural aluminium. Other than 26Al, all radioisotopes have half-lives under 7 minutes, most under a second. The standard atomic weight is . 26Al is produced from argon in the atmosphere by spallation caused by cosmic-ray protons. Aluminium isotopes have found practical application in dating marine sediments, manganese nodules, glacial ice, quartz in rock exposures, and meteorites. The ratio of 26Al to 10Be has been used to study the role of sediment transport, deposition, and storage, as well as burial times, and erosion, on 105 to 106 year time scales. 26Al has also played a significant role in the study of meteorites. List of isotopes , - , 21Al?This isotope has not yet been confirmed experimentally; given data is inferred or estimated from periodic trends ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Typhoon Lee
Typhoon Lee (; born 1948) is an astrophysicist and geochemist at Academia Sinica, Taiwan, where he specializes in isotope geochemistry and nuclear astrophysics . Lee received his Ph.D. in astronomy at the University of Texas in 1977. His honors include the Robert J. Trumpler Award in 1978 from the Astronomical Society of the Pacific, and Outstanding Researcher Awards from the National Science Council The National Science and Technology Council (NSTC; ) is a statutory agency of Executive Yuan of the Republic of China (Taiwan) for the promotion and funding of academic research, development of science and technology and science parks. NSTC is ... in 1985-87 and 1988–90. A selection of his publications includes: *''X-wind, Refractory IDPs and Cometary Nuclei'', 1999, in Proc. IAU Colloquium 168, Astro. Soc. Pacific, San Francisco. *''Proto-stellar Cosmic Rays and Extinct Radioactivities in Meteorites'', 1998, Ap. J. 506, 898–912. *''Coral Sr/Ca as a High Precisio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harold Urey
Harold Clayton Urey ( ; April 29, 1893 – January 5, 1981) was an American physical chemist whose pioneering work on isotopes earned him the Nobel Prize in Chemistry in 1934 for the discovery of deuterium. He played a significant role in the development of the atom bomb, as well as contributing to theories on the development of organic life from non-living matter. Born in Walkerton, Indiana, Urey studied thermodynamics under Gilbert N. Lewis at the University of California, Berkeley. After he received his PhD in 1923, he was awarded a fellowship by the American-Scandinavian Foundation to study at the Niels Bohr Institute in Copenhagen. He was a research associate at Johns Hopkins University before becoming an associate professor of Chemistry at Columbia University. 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. He he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
K–Ar Dating
Potassium–argon dating, abbreviated K–Ar dating, is a radiometric dating method used in geochronology and archaeology. It is based on measurement of the product of the radioactive decay of an isotope of potassium (K) into argon (Ar). Potassium is a common element found in many materials, such as feldspars, micas, clay minerals, tephra, and evaporites. In these materials, the decay product is able to escape the liquid (molten) rock, but starts to accumulate when the rock solidifies ( recrystallizes). The amount of argon sublimation that occurs is a function of the purity of the sample, the composition of the mother material, and a number of other factors. These factors introduce error limits on the upper and lower bounds of dating, so that the final determination of age is reliant on the environmental factors during formation, melting, and exposure to decreased pressure or open air. Time since recrystallization is calculated by measuring the ratio of the amount of accumulated to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
