Start Definition radiocarbon dating

Definition radiocarbon dating

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

Here’s an example using the simplest atom, hydrogen. Carbon-14 is an unstable isotope of carbon that will eventually decay at a known rate to become carbon-12.

Radiocarbon dating uses isotopes of the element carbon. Cosmic rays – high energy particles from beyond the solar system – bombard Earth’s upper atmosphere continually, in the process creating the unstable carbon-14. Because it’s unstable, carbon-14 will eventually decay back to carbon-12 isotopes.

This means that although they are very similar chemically, they have different masses.

The total mass of the isotope is indicated by the numerical superscript.

Carbon combines with other elements in complex ways to form the molecules that make up our bodies.

Most carbon on Earth is not radioactive, but a very small percentage is.

However, scientists can look at the decay of other elements in these objects allowing them to date them up to 2.2 billion years.

Rachel Wood does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.

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.

The following article is primarily based on a discussion of radiocarbon dating found in The Biblical Chronologist Volume 5, Number 1. Radiocarbon dating is based on a few relatively simple principles. The vast majority of these are C (pronounced "c twelve"), the stable isotope of carbon.

It can be used on objects as old as about 62,000 years.