Bachelor of Arts in Physics, 1982, Swarthmore College; Bachelor of Arts in Mathematics, 1984, M.A. 1990, University of Cambridge; M.Phil. History and Philosophy of Science 1986, University of Cambridge, Cambridge, England; Ph.D. in Astronomy (Planetary Science) from Cornell University, 1991; semi finalist in NASA group 16 selection; currently Co-Director of Stanford's Center for International Security and Cooperation, and Associate Professor in the Department of Geological and Environmental Sciences.