Sharpen Your Mind: Carbon Dating

Posted by Jerry Lopper Mar 22, 2007

All living organisms, plants, animals, insects, and humans contain carbon. Carbon is normally a very stable molecule, but natural cosmic radiation creates a small amount of an isotope of carbon, carbon-14, which is not stable. Both the stable form of carbon (carbon-12) and carbon-14 are present in all living organisms.

Though carbon-14 naturally decays because of its instability, a living organism replenishes it through feeding. When an organism dies, however, the carbon-14 is no longer replenished and continues to decay. The decay rate of carbon-14 is known and constant; it will be reduced by one-half in 5,730 years.

Scientists use this known decay rate to measure the time at which an organism ceased to live by measuring the ratio of carbon-14 to stable carbon (carbon-12) still present. If a dead object has half the ratio as a similar live object, the object must have died 5,370 years ago.

Interesting Trivia:

Radioactive uranium has a half-life of 704 million years.

Potassium-40, naturally found in the human body, has a half-life of 1.3 billion years.

For more mind sharpening material see Mind & Attitude in the index.

Source: The Intellectual Devotional, David S. Kidder & Noah D. Oppenheim