DANIEL J. SCHEERES is a professor in the Department of Aerospace Engineering Sciences at the University of Colorado, Boulder, and a member of the Colorado Center for Astrodynamics Research. Prior to this, he held faculty positions in aerospace engineering at the University of Michigan (1999-2008) and Iowa State University (1997-1999) and was a member of the technical staff in the Navigation Systems Section at the California Institute of Technology’s Jet Propulsion Laboratory (1992-1997). His research interests include the dynamics, control and navigation of spacecraft trajectories; the design of space missions; optimal control; planetary science; celestial mechanics; and dynamical astronomy. He is a fellow of the American Astronautical Society (AAS), and is an associate fellow of the AIAA. He serves on the AAS Space Flight Mechanics Committee and the AIAA Astrodynamics Technical Committee. He is a member of the Celestial Mechanics Institute and the IAU. He is an associate editor for Celestial Mechanics and Dynamical Astronomy, the Journal of Nonlinear Science, the Journal of Guidance, Control and Dynamics, and the Journal of the Astronautical Sciences. He is the recipient of two NASA Group Awards for his work on the NEAR mission, and Asteroid 8887 is named “Scheeres” in recognition of his contributions to the scientific understanding of the dynamical environment about asteroids. He was awarded his Ph.D., M.S.E., and B.S.E. degrees in aerospace engineering from the University of Michigan, and holds a B.S. in letters and engineering from Calvin College.
SARAH T. STEWART-MUKHOPADHYAY is the John L. Loeb Associate Professor of the Natural Sciences in the Department of Earth and Planetary Sciences at Harvard University. She has more than 12 years of experience in studying impact cratering and conducting shock wave experiments. In 2004, she established the Shock Compression Laboratory at Harvard that focuses on Earth and planetary science topics and on training new experimentalists in shock wave research. Her current research includes experimental programs on shock temperature and the effects of porosity and volatility on shock wave propagation. Dr. Stewart also leads the development of numerical techniques for simulations of impact events. Her current work in that area includes improvements in equations of state and strength models in the shock physics code CTH. Her research interests include the experimental and computational study of impact processes to interpret the resurfacing history, physical properties, and internal structure of planets. She is a recipient of a Presidential Early Career Award for Scientists and Engineers. Dr. Stewart received a B.A. in astronomy and astrophysics and physics from Harvard University in 1995 and a Ph.D. in planetary sciences (minor in astrophysics) from the California Institute of Technology in 2002.
KATHRYN C. THORNTON is assistant dean of and professor in the School of Engineering and Applied Science at the University of Virginia. Dr. Thornton has extensive human spaceflight experience and served for 12 years as a NASA astronaut, flying on four shuttle missions and performing extravehicular activities (i.e., spacewalks) on two of them. She also headed the NASA Johnson Space Center education working group, which coordinated the educational outreach activities of astronauts and professional educators working under the “Teaching from Space” contract with Oklahoma State University. Before becoming a member of the space program, she coauthored more than 30 scientific publications and was a staff physicist for the U.S. Army Foreign Science and Technology Center for 4 years. Dr. Thornton has previously served on the NRC Aeronautics and Space Engineering Board, the Committee for Technological Literacy, and the Committee on Meeting the Workforce Needs for the National Vision for Space Exploration.
DWAYNE A. DAY, Study Director, a program officer for the NRC’s Space Studies Board (SSB), has a Ph.D. in political science from the George Washington University and previously served as an investigator for the Columbia Accident Investigation Board. He was on the staff of the Congressional Budget Office and also worked for the Space Policy Institute at the George Washington University. He has held Guggenheim and Verville fellowships and is an associate editor of the German spaceflight magazine Raumfahrt Concrete, in addition to writing for such publications as Novosti Kosmonavtiki (Russia), Spaceflight, and Space Chronicle (United Kingdom). He has served as study director for several NRC reports, including Space Radiation Hazards and the Vision for Space Explora-