Chief theoretician of Soviet astronautics in the 1960s. Keldysh studied physics and mathematics at Moscow University, obtaining his Ph.D. in 1938. He worked for many years in a variety of positions at the Central Institute of Aerohydrodynamics, Moscow University, and the Steklov Mathematical Institute. In 1960-61 he served as vice president of the Soviet Academy of Sciences, and thereafter as its president until 1975.
