Named in honor of Jukka Piironen, astronomer at the Finnish Meteorological Institute, Helsinki. Working with the discoverer, Piironen made accurate lightcurve observations of a number of brighter minor planets. Subsequently, he was involved in the physical interpretation of such lightcurves by studying the behavior of rotating models in the laboratory. In Turku he participated in the grinding and figuring of the 2.5-m mirror for the Nordic Optical Telescope {see planet  (2857)}, and he worked on aspects of the Soviet Phobos mission. (M 12977) _ _.