Willard Frank Libby (December 17, 1908 – September 8, 1980) was an American physical chemist noted for his role in the 1949 development of radiocarbon dating, a process which revolutionized archaeology and palaeontology.

During World War II he worked in the Manhattan Project's Substitute Alloy Materials (SAM) Laboratories at Columbia University, developing the gaseous diffusion process for uranium enrichment.

After the war, Libby accepted a professorship at the University of Chicago's Institute for Nuclear Studies, where he developed the technique for dating organic compounds using carbon-14.

Libby resigned from the AEC in 1959 to become professor of chemistry at University of California, Los Angeles (UCLA), a position he held until his retirement in 1976.

[5] Libby, who grew to be 6 feet 2 inches (188 cm) tall, played tackle on the high school football team.

[6] In 1927 he entered the University of California, Berkeley, where he received his BS in 1931, and his PhD in 1933,[1] writing his doctoral thesis on the "Radioactivity of ordinary elements, especially samarium and neodymium: method of detection"[7] under the supervision of Wendell Mitchell Latimer.

[8] Independently of the work of George de Hevesy and Max Pahl, he discovered that the natural long-lived isotopes of samarium primarily decay by emission of alpha particles.

[6] On December 8, 1941, the day after the Japanese attack on Pearl Harbor brought the United States into World War II, Libby volunteered his services to Nobel Prize laureate Harold Urey.

"[6] After the war, Libby accepted an offer from the University of Chicago of a professorship in the chemistry department at the new Institute for Nuclear Studies.

[27] Libby realized that when plants and animals die they cease to ingest fresh carbon-14, thereby giving any organic compound a built-in nuclear clock.

[26] Atomic Energy Commission (AEC) Chairman Gordon Dean appointed Libby to its influential General Advisory Committee (GAC) in 1950.

Staunchly conservative politically, he was one of the few scientists who sided with Edward Teller rather than Robert Oppenheimer during the debate on whether it was wise to pursue a crash program to develop the hydrogen bomb.

[6][31] As the only scientist among the five AEC commissioners, it fell to Libby to defend the Eisenhower administration's stance on atmospheric nuclear testing.

[9][33] In January 1956, he publicly revealed the existence of Project Sunshine, a series of secret research studies to ascertain the impact of radioactive fallout on the world's population that he had initiated in 1953 while serving on the GAC.

The project caused controversy after it was revealed to the public and with the revelation it was found out that much of the research involved stealing the bodies of dead children without the parents' consent and doing radioactive experiments on them.

[35] Libby resigned from the AEC in 1959, and he became professor of chemistry at University of California, Los Angeles, a position he held until his retirement in 1976.

[9] He established a research program to investigate heterogeneous catalysis with the idea of reducing emissions from motor vehicles through more complete fuel combustion.

[38] Analy High School library has a mural of Libby,[5] and a Sebastopol city park and a nearby highway are named in his honor.

[2][44] Libby died at the UCLA Medical Center in Los Angeles on September 8, 1980, from a blood clot in his lung complicated by pneumonia.