Donald U. Wise is a research associate at Franklin and Marshall College and professor emeritus at the University of Massachusetts, where he chaired the Department of Geology and Geography from 1984 to 1988. He earned his Ph.D. in 1957 from Princeton University and joined the UMass faculty in 1969. His wide-ranging research interests have included Appalachian and Rocky Mountain tectonics, fracture mechanics, global sea-level controls, Martian tectonics and the origin of the moon. Around the time of the first lunar landing in 1968–69, he served as chief scientist and deputy director of one of NASA’s offices of lunar exploration. Address: Department of Geosciences, Franklin and Marshall College, Lancaster, PA 17604. Internet: d_wise@acad.fandm.edu.