Named in honor of Jeffrey B. Plescia, a versatile scientist at the Jet Propulsion Laboratory who works with equal ease in geology, geophysics and planetary science. He has been a leading investigator of the cratering history of the satellites of Jupiter, Saturn and Uranus. More recently, Plescia has pursued gravity studies of terrestrial impact craters, including Upheaval Dome in Utah, the Manson structure of Iowa, and the Mt. Toondina, Kelly West and Teague Ring structures in Australia. (M 29671) _ _.