February 27: Carbon-14

Carbon-14, the radioactive isotope used by plant biologists and archaeologists to carbon-date materials up to 60,000 years old, was discovered on this date in 1940 by Martin Kamen and Sam Ruben at the University of California Radiation Laboratory in Berkeley. Kamen would be assigned to the Manhattan Project in 1943 and then suspended on suspicion of passing nuclear secrets to the USSR; a ten-year effort to clear his name (during which he attempted suicide) ended in restoration of his passport and a successful libel suit against the Chicago Tribune for naming him as a suspected spy. Kamen wrote a memoir, Radiant Science, Dark Politics, and won the Enrico Fermi Award in 1996. Sam Ruben (born Charles Rubenstein) would die in a lab accident while doing wartime research on poison gas. The actual radiocarbon dating technique that relies on Carbon-14 was developed by scientists at the University of Chicago in 1949 and yielded a 1960 Nobel Prize in Chemistry for Willard Libby.

“Although my scientific career burgeoned . . . there was a pall overlaying it. It would be years before it dissipated.” —Martin Kamen