The application of Accelerator Mass Spectrometry (AMS) for radiocarbon dating in the late 1970s was also a major achievement.
Compared to conventional radiocarbon techniques such as Libby's solid carbon counting, the gas counting method popular in the mid-1950s, or liquid scintillation (LS) counting, AMS permitted the dating of much smaller sized samples with even greater precision.
But, as is clear even from the very brief discussion in the previous paragraph, radiocarbon dating can say nothing one way or the other about whether the earth is many millions of years old, since such dates are far beyond this method's range of resolution.
However, cosmic radiation constantly collides with atoms in the upper atmosphere.
Part of the result of these collisions is the production of radiocarbon (C, pronounced "c fourteen"), carbon atoms which are chemically the same as stable carbon, but have two extra neutrons.
It subsequently evolved into the most powerful method of dating late Pleistocene and Holocene artifacts and geologic events up to about 50,000 years in age.
The radiocarbon method is applied in many different scientific fields, including archeology, geology, oceanography, hydrology, atmospheric science, and paleoclimatology.
When a plant or animal organism dies, however, the exchange of radiocarbon from the atmosphere and the biosphere stops, and the amount of radiocarbon gradually decreases, with a half-life of approximately 5730 years.
Because of this relatively short half-life, radiocarbon is useful for dating items of a relatively recent vintage, as far back as roughly 50,000 years before the present epoch.The laboratory has an "open-door" policy for all existing and potential users of its facilities at all stages of their research projects, and collaboration is strongly encouraged. Radiocarbon decays slowly in a living organism, and the amount lost is continually replenished as long as the organism takes in air or food.The atmosphere contains many stable carbon atoms and relatively few radiocarbon atoms.The ratio of radiocarbon to stable carbon atoms in the atmosphere has varied in the past.For his leadership, Libby received the Nobel Prize in Chemistry in 1960.