Libby, Willard Frank (1908–1980)

US chemist who was awarded the Nobel Prize for Chemistry in 1960 for his development in 1947 of radiocarbon dating as a means of determining the age of organic or fossilized material.

Libby was born in Grand Valley, Colorado, and studied at the University of California, Berkeley. During World War II he worked on the development of the atomic bomb (the Manhattan Project). In 1945 he became professor at the University of Chicago's Institute for Nuclear Studies. He was a member of the US Atomic Energy Commission 1954–59, and then became director of the Institute of Geophysics at the University of California.

Having worked on the separation of uranium isotopes for producing fissionable uranium-238 for the atomic bomb, he turned his attention to carbon-14, a radioactive isotope that occurs in the tissues of all plants and animals, decaying at a steady rate after their death. He and his co-workers accurately dated ancient Egyptian relics by measuring the amount of radiocarbon they contained, using a sensitive Geiger counter. By 1947 they had developed the technique so that it could date objects up to 50,000 years old.