Thomas Gold (May 22, 1920 – June 22, 2004) was an Austrian-born astrophysicist, a professor of astronomy at Cornell University, a member of the U.S. National Academy of Sciences, and a Fellow of the Royal Society (London). Gold was one of three young Cambridge scientists who in the 1950s proposed the now mostly abandoned 'steady state' hypothesis of the universe. Gold's work crossed academic and scientific boundaries, into biophysics, astronomy, aerospace engineering, and geophysics.