 Previously, she held positions as the Chief Scientist of the W.M.Keck Observatory, Director of the Solar System Exploration Division at NASA Goddard Space Flight Center, Director of the Origins Program at NASA Jet Propulsion Laboratory, and Director of the Universe Division at NASA Headquarters.She earned a bachelor's degree in astronomy and physics from the University of Wisconsin-Madison and a doctorate in astrophysics from New York University, and has published more than 80 papers on extragalactic astronomy.