Named in memory of Harold Spencer Jones (1890–1960), successively astronomical assistant at the Royal Greenwich Observatory, H.M. astronomer at the Cape of Good Hope, and Astronomer Royal (1933–1955). He also served as president of the IAU (1945–1948). His work was devoted to fundamental positional astronomy, and he conclusively demonstrated that the small residuals in the apparent motions of the planets were due to the irregular rotation of the Earth. He led the worldwide effort to determine the length of the astronomical unit by triangulating the distance to (433) Eros when it passed near the Earth in 1930–31. (M 16041) _ _.