Named in honor of Charles C. Counselman III (1943– ), professor of planetary science at the Massachusetts Institute of Technology. As a scientist involved with the Pioneer Venus mission, he used interferometric measurements of the spacecraft multiprobes to deduce the vertical distribution of Venusian wind velocities. More recently, he has pioneered the use of Global Positioning System satellites to achieve very high precision geodetic measurements of the surface of the earth. Counselman is also a dedicated teacher and is particularly devoted to student advising and the instruction of planetary astronomy laboratory courses. (M 27125) _ _.