What is radiocarbon dating
This technique works well for materials up to around 50,000 years old.Each radioactive isotope decays by a fixed amount, and this amount is called the half-life.Atmospheric carbon-14 rapidly reacts with oxygen in air to form carbon dioxide and enters the carbon cycle.Plants take in carbon dioxide through photosynthesis and the carbon-14 makes its way up the food chain and into all living organisms.
By measuring the amount of carbon-14 left in the organism, it's possible to work out how old it is.
Once the organism dies, the amount of carbon-14 reduces by the fixed half-life - or the time required for half of the original sample of radioactive nuclei to decay - of 5,730 years, and can be measured by scientists for up to 10 half-lives.
Measuring the amount of radioactive carbon-14 remaining makes it possible to work out how old the artifact is, whether it's a fossilized skeleton or a magnificent piece of artwork.
You might remember that it was mentioned earlier that the amount of carbon-14 in living things is the same as the atmosphere.
Once they die, they stop taking in carbon-14, and the amount present starts to decrease at a constant half-life rate.