Radiocarbon dating is a scientific method used to determine the age of an object containing organic material by measuring the concentration of carbon-14 (¹⁴C), a radioactive isotope of carbon.
Here's how it works:
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Carbon Isotopes: Carbon exists in different isotopes, with carbon-12 (¹²C) and carbon-14 (¹⁴C) being the most common. Carbon-14 is formed in the atmosphere when nitrogen-14 (¹⁴N) absorbs cosmic rays.
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Incorporation into Organisms: Carbon dioxide in the atmosphere gets absorbed by plants during photosynthesis, and animals then consume the plants. As a result, all living organisms incorporate a stable ratio of ¹²C to ¹⁴C.
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Decay After Death: When an organism dies, it stops taking in carbon, and the ¹⁴C within its tissues begins to decay into nitrogen-14 (¹⁴N) at a known half-life of about 5,730 years. By measuring the remaining amount of ¹⁴C in a sample and comparing it to the expected amount in the environment, scientists can calculate the time since the organism's death.
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Dating Range: Radiocarbon dating is effective for dating samples that are up to about 50,000 years old, with precision diminishing for older samples.
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Applications: This method is widely used in archaeology, geology, and environmental science to date ancient organic materials, artifacts, fossils, and even ice cores.
Overall, radiocarbon dating has become a crucial tool in understanding historical timelines and the age of ancient biological materials.