Radio-carbon dating is a scientific method that estimates the age of organic materials by measuring the proportion of carbon-14 they contain. Cosmic rays interact with nitrogen in the Earth’s atmosphere to create carbon-14, a radioactive isotope of carbon with a known time it takes to decay to half its amount (half life) of about 5,730 years. Living organisms absorb carbon-14 from the environment, which becomes incorporated into their bodies and bones. When an organism dies, it stops absorbing carbon and the carbon-14 in its body begins to decay into other atoms. The proportion of carbon-14 in a sample decreases exponentially over time as it radio-decays. Scientists can estimate how long ago the organism died by using the half life of Carbon-14.
