Named in honor of Raynor L. Duncombe {1917– }, astronomer at the University of Texas, on the occasion of his seventieth birthday. A leader in positional and dynamical astronomy, he has pursued wide-ranging research that has included the study of the motions of major planets, minor planets and satellites; he was a pioneer in artificial-satellite orbit determination and in the use of digital computers in astronomy; and he has recently been involved with the astrometric uses of the Hubble Space Telescope as a member of the Astrometry Team. He served as director of the U.S. Nautical Almanac Office from 1963 to 1975, was the first chairman of the American Astronomical Society’s Division on Dynamical Astronomy and for a number of years the executive editor of Celestial Mechanics. (M 11750) _ _.