The tissue of every organism absorbs the C14 isotope from the atmosphere. Libby in 1946–47, the carbon-14 method is the best known means of dating organic material.When the organism dies, the flow of C14 is interrupted and any C14 absorbed during its life gradually disappears – half of it every 5730 years (the half-life of the isotope).

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View the full list Radiocarbon dating has transformed our understanding of the past 50,000 years.

Professor Willard Libby produced the first radiocarbon dates in 1949 and was later awarded the Nobel Prize for his efforts.

While the lighter isotopes C has decayed that what remains can no longer be measured. In 5,730 years half of the C in the atmosphere, and therefore in plants and animals, has not always been constant.

Radioactive decay can be used as a “clock” because it is unaffected by physical (e.g. For instance, the amount varies according to how many cosmic rays reach Earth.

This is affected by solar activity and the earth’s magnetic field.

Radiocarbon dating works by comparing the three different isotopes of carbon.

Isotopes of a particular element have the same number of protons in their nucleus, but different numbers of neutrons.