Named in honor of Karri O. Muinonen, planetary scientist at the Lowell Observatory. Formerly at the observatory and astrophysics laboratory of the University of Helsinki, Muinonen worked on the light-scattering properties of inhomogeneous media and independently originated the suggestion that coherent backscattering is responsible for both the opposition spike and the negative polarization of light from the surfaces of many atmosphereless bodies. He has since turned to the study of the spatial distribution of minor planets, particularly the population of planet crossers that might pose a hazard to the earth, and he has devised a new way of assessing the uncertainty of minor planet orbits, and hence ephemerides. (M 18461) _ _.