Scientific american carbon dating
Radiocarbon, or carbon 14, is an isotope of the element carbon that is unstable and weakly radioactive. Carbon 14 is continually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen 14 atoms.It is rapidly oxidized in air to form carbon dioxide and enters the global carbon cycle.A T-shirt made in 2050 could look exactly like one worn by William the Conqueror a thousand years earlier to someone using radiocarbon dating if emissions continue under a business-as-usual scenario.By 2100, a dead plant could be almost identical to the Dead Sea scrolls, which are more than 2,000 years old.
Levels of carbon 14 from nuclear explosions peaked in the mid-1960s, when test ban treaties began to take hold.
That's where two decades of atomic bomb testing can offer clues.
Radioactive carbon released into the atmosphere during the blasts and then absorbed by grapes can be used to accurately determine wine vintages, according to a study presented March 21 at the National Meeting of the American Chemical Society.
As scrolls, plant-based paints or cotton shirts age over thousands of years, the radioactive carbon-14 that naturally appears in organic objects gradually decays.
The amount of carbon-14 decreases relative to the amount of normal carbon.