BA, Stanford; PhD, Physics, California Institute of Tech. Former: Scientist and Deputy Group Leader, Earth and Space Sciences Div., Los Alamos Nat'l Lab.; Head, Department of Astronomy and Astrophysics, Pennsylvania State University; Chief Scientist, NASA; Vice-Chancellor, Research and Professor of Physics, University of California, Santa Barbara; Chancellor and Professor of Physics and Astronomy, University of California, Riverside; President and current President Emerita, Purdue University. Currently, Director, National Science Foundation. Former: Chair, Board of Regents, Smithsonian Institution; Member, Board of Trustees, Mayo Clinic; Member, National Science Board (NSB).