Berkelium is a synthetic element in the periodic table that has the symbol Bk and atomic number 97. It is the eighth member of the actinide transition series. It was first synthesized by Glenn T. Seaborg, Albert Ghiorso, Stanley G. Thompson, and Kenneth Street, Jr. at the University of California, Berkeley (after which it was also named) in December 1949. They did this by bombarding 241 Am with helium ions.