Radiocarbon dating

What is Radiocarbon Dating?

Radiocarbon dating is a special way to find out how old something is if it was once alive, like a piece of wood or bone. It helps us learn when plants and animals lived long ago by looking at a tiny bit of a special kind of carbon called carbon-14.

How Does It Work?

The idea for radiocarbon dating began in the late 1940s at the University of Chicago by Willard Libby. Carbon-14 is made in the Earth's atmosphere when cosmic rays hit nitrogen. It then becomes carbon dioxide, which plants take in through photosynthesis. Animals get it by eating plants. When a plant or animal dies, it stops getting new carbon, and the carbon-14 inside slowly fades away. By measuring how much carbon-14 is left, we can estimate when the organism died. The half-life of carbon-14 is about 5,730 years, so this method works best for objects up to about 50,000 years old.

Radiocarbon dating helped verify the authenticity of the Dead Sea Scrolls.

Why It Matters

Radiocarbon dating changed the field of archaeology greatly. It lets experts date old things more accurately and compare events from far apart. It helped date big changes in history, like the end of the last ice age and the start of the Neolithic and Bronze Age in different places. Because of this, some call it the “radiocarbon revolution.”