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From Taylor, 1987
The radiocarbon dating process was developed by physicist Willard F. Libby (please see photo) in 1948 with the help of two scientists, Dr. E.C. Anderson and Dr. James R. Arnold. Libby was born on December 17, 1908 in Grand Valley, Colorado. He taught at the University of California-Berkeley from 1933-1941. In 1941 Libby began working on the Manhattan Project, a top secret project supported by the United States’ government. The purpose of the Manhattan Project was to develop an atomic bomb. The scientists involved in the project succeeded and their efforts directly correlated to the end of WWII. Libby’s discovery of radiocarbon coincidentally took place at the University of Chicago, the same place where the beginnings of the atom bomb occurred. Both the atom bomb and radiocarbon dating influence the field of science even today. In 1960 Libby won the Nobel Prize in Chemistry, "for his method to use Carbon-14 for age determinations in archaeology, geology, and other bran!
ches of science." Libby died in 1980.
Radiocarbon dating is a technique in which scientists can answer many questions about the past in the fields of archaeology, anthropology, atmospheric science, biomedicine, climatology, geology, oceanography, and palaeoclimatology. Scientists, with the help of the radiocarbon dating process, are able to date objects such as skeletons, fossils, and ancient artifacts like pottery and tools. The dates of these objects allow scientists to show how long ago a civilization (i.e. Incans, Sumerians, etc.…) lived, how old something is, and ultimately, is the bible correct.
A normal carbon atom, Carbon-12, has six protons, six neutrons, and six electrons. A Carbon-14 isotope is extremely unstable, and therefore, radioactive. Carbon-12 accounts for 98.89% of all carbon present. Carbon-13 accounts for 1.11% and C-14, radiocarbon is .0000000010% of all carbon in the world. From these numbers, it can be determined that for every atom of Carbon-14, there are1,000,000,000,000 Carbon-12 atoms out there. Carbon-14 has two extra neutrons, brining its neutron total to eight. Carbon-14 returns to its stable form of Carbon-12 through a process of decay.
The radiocarbon process is based on the rate of decay of the unstable Carbon-14 isotope. Carbon-14 is formed in the upper atmosphere of the earth when cosmic rays and Nirogen-14 interact. The reaction is:
(where n is a neutron and p is a proton)
Scientists believe that these cosmic rays have been bombarding the earth’s upper atmosphere since the beginning of time, while the amount of nitrogen in the earth’s upper atmosphere has remained constant as well. The formation of Carbon-14 is thought to occur at a constant rate. Thus, for Carbon-14 to have occurred at a constant rate since the beginning of time, so must have the amount of cosmic rays and nitrogen in the earth’s atmosphere. The current ratio of Carbon-14 to other forms of carbon is known, though scientists are not sure whether that ratio has been the same for all of time. The do, however, say that the radiocarbon process is accurate in dating objects back to at least 50,000 years.
The Carbon-14 formed in the upper atmosphere of the earth is rapidly oxidized into 14CO2 and then is able to enter the earth’s plant and animal life through the process of photosynthesis, by way of the food chain, and also enters the earth’s oceans in an atmospheric exchange and as a dissolved carbonate. This rapid dispersal of Carbon-14 into the earth’s atmosphere has been demonstrated by measurements of radioactive carbon that has been produced from thermonuclear bomb testing. Plants and animals, which utilize carbon in biological food chains, will at one time or another, take up Carbon-14. When this plant or animal dies, there is no more intake of Carbon-14, or any other substance for that matter. This is when the process of carbon dating begins.
Libby and other scientists discovered that the decay of Carbon-14 occurs at a constant rate. The half-life of Carbon-14, they said, was 5,568+/-30 years. This is known as the Libby half-life. If, for example, a brontosaurus died, half of its Carbon-14 would be gone 5,568 years after his death. Leaving him with 50% of its original total. Another
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Radioactivity, Isotopes of carbon, Conservation and restoration, Radiometric dating, Nuclear physics, Radiocarbon dating, Carbon-14, Carbon, Willard Libby, Radionuclide, Cosmic ray, Isotope
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