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Researchers have observed that when cells divide, the cells can use some of the carbon 14 to build deoxyribonucleic acid (DNA), a phenomenon that serves as a birthmark for new cells.
While radioactivity from tritium halves every 12.3 years, it takes almost 6,000 for the same thing to happen with Carbon 14.
Aboveground nuclear bomb tests during the Cold War led to skyrocketing levels of the radioactive isotope carbon 14 in the environment.
Hence fossils cannot be many thousands of years old, or there would be no detectable carbon 14.
As examples, the half-life of radioactive carbon, carbon 14, is 5730 years; and of radioactive potassium, potassium 40, is 1.25 billion years.
A brief review of Carbon 14 analysis will explain why the authors could make such claims.
At the time of the rupture, around 10:15 a.m., carbon 14 dissolved in toluene and other volatile fluids was being burned.
The importance of this site appeared as soon as the Carbon 14 dates came back, showing the settlement of Lapita and the manufacture of dentate stamped pots as early as 800 years BC, a period far older than the then-supposed date of first human colonisation of the Pacific.
The initial results, published on November 9, indicate that radioactive gas is present, particularly Carbon 14 and Krypton 85 - a rare radioactive gas produced by the fission of uranium.
Mr Timothy Jull, who led the research at the University of Arizona at Tucson, said: "The organic material contains 14C (the carbon 14 isotope) and the carbonate doesn't because the carbonate came from somewhere in space, presumably Mars, and the organic material is a recent addition which took place while the meteorite was sitting on the ice.