Together with G. E. Uhlenbeck, Dutch-American physicist Samuel A. Goudsmit (1902-1978) formulated the concept of electron spin. This led to major changes in atomic theory and quantum mechanics. The name was suggested by W. A. Fröger.
Discovered on 24-9-1960 in Palomar by van Houten, C. J., van Houten-Groeneveld, I., Gehrels, T.