Libby, Willard Frank

Willard Libby was an American chemist who won the 1960 Nobel Prize in Chemistry for the discovery of radiocarbon dating, a process that revolutionized archaeology and several other branches of science. Carbon-14 is an unstable radioactive isotope that decays at a measurable rate upon the death of an organism. Libby was able to determine the age of organic artifacts by measuring the amount of remaining Carbon-14. He tested his process on objects of known age, such as timbers from Egyptian tombs. The tests proved reliable, and it was assumed that this technique was accurate for objects up to 50,000 years of age. Later, it was realized that this technique was accurate up to 70,000 years. He also discovered that tritium could be used for dating water, and therefore wine.  

During World War II, he worked on the Manhattan Project at Columbia University with Nobel laureate Harold Urey. Libby was responsible for the gaseous diffusion separation and enrichment of Uranium-235 that was used in the atomic bomb detonated over Hiroshima, Japan.

In 1954, he was appointed to the U.S. Atomic Energy Commission.


  • Cleveland, Cutler (Lead Author); Peter Saundry (Topic Editor). 2008. "Libby, Willard Frank." In: Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D.C.: Environmental Information Coalition, National Council for Science and the Environment). [First published in the Encyclopedia of Earth September 15, 2006; Last revised August 21, 2008; Retrieved April 12, 2009].
  • Wikipedia Contributors, Willard Libby, Wikipedia The Free Encyclopedia, Accessed 12 April 2009.

Terms of Use:

This article uses material from the Encyclopedia of Earth. The Author(s) and Editor(s) listed with this article may have significantly modified the content derived from the Encyclopedia of Earth with original content or with content drawn from other sources. The current version of the cited Encyclopedia of Earth article may differ from the version that existed on the date of access. Text in this article available under the Creative Commons Attribution-Share Alike 2.5 Generic License: