Carbon-14 is a radioactive isotope used in carbon dating to determine the age of fossils and ancient antiquities.

The isotope itself was discovered by a pair of UC Berkley scientists with two major things in common—a passion for chemistry, and Judaism.


Martin Kamen was born in 1913 in Toronto and showed an early love of science. After earning his PhD in chemistry he joined the staff at the University of California Radiation Laboratory in Berkley, working without pay for six months just to secure the position.

Sam Ruben, meanwhile, was pursuing a similar path. Born in 1913 in San Francisco, Ruben attended UC Berkley as a student, earning his PhD then taking a position as an instructor at his alma mater.

By the time the two men ended up in the same radioactivity lab, the focus was on carbon patterns. Kamen was in charge in overseeing the prep and distribution of products made in cyclotrons, and on February 27, 1940, the duo decided to use graphite in the device to see if a radioactive isotope could be created.

The result was carbon-14, a tracer able to map the biochemical reactions in an object, giving scientists a new, effective way to date artifacts. In 1949 carbon dating would be invented, and the technique is still widely used today.

Kamen moved on to Brandeis University then UC San Diego. He died August 31, 2002 at the age of 89. For his efforts, Kamen was awarded the Enrico Fermi Award in 1996 and the Albert Einstein World Award of Science in 1989.

Ruben was later recruited for research during World War II, but he died in 1943, after exposure to phosgene in a lab accident.