1. National Optical Astronomy Observatories, Tucson, AZ 85719, USA.
2. Planetary Science Institute—Science Applications International Corporation (SAIC), Tucson, AZ 85705, USA.
3. Department of Astronomy, Cornell University, Ithaca, NY 14853, USA.
4. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
5. Department of Geology, Arizona State University, Tempe, AZ 85287-1404, USA.
6. Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 87721, USA.
7. Department of Geology, Brown University, Providence, RI 02912, USA.
8. United States Geological Survey, Flagstaff, AZ 86001, USA.
9. National Aeronautics and Space Administration Ames Research Center, Moffet Field, CA 94035, USA.
10. RAND, Santa Monica, CA 90406, USA.
11. United States Geological Survey, Menlo Park, CA 94025, USA.
12. Deutsche Forschungsanstalt für Luft und Raumfahrt, Institute for Planetary Exploration, Berlin, Germany
13. Institute of Geophysics, University of Hawaii, Honolulu, HI 96822, USA.
14. Institute for Space and Terrestrial Science, Concord, Ontario, Canada L4K 3C8
15. California Institute of Technology, Pasadena, CA 91125, USA.
16. National Aeronautics and Space Administration, Washington, DC 20546, USA.