What Is Radiocarbon Dating?

All living organisms absorb carbon from the environment, including a small proportion of radioactive carbon-14 (¹⁴C), which is continuously produced in the atmosphere by cosmic rays. When an organism dies, it stops taking in new carbon, and the ¹⁴C it contains decays at a known rate — its half-life is 5,730 years. By measuring how much ¹⁴C remains in a sample relative to stable carbon-12, scientists can calculate the time since death. The technique is reliable for materials up to about 50,000 years old and has been essential in archaeology, geology, and climate science.