1. United States Geological Survey, 2255 North Gemini Drive, Flagstaff, AZ 86001, USA.
2. Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238, USA.
3. Department of Geological Sciences, University of Tennessee, 306 Geological Sciences Building, Knoxville, TN 37996, USA.
4. Department of Planetary Science, Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA.
5. Jet Propulsion Laboratory (JPL), California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, USA.
6. DLR Institute of Space Sensor Technology and Planetary Exploration, Rutherfordstrasse, 2D-12489 Berlin, Germany.
7. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA.
8. Department of Space Studies, Southwest Research Institute, 1050 Walnut Street No. 426, Boulder, CO 80302, USA.
9. Max-Planck-Institut für Aeronomie, Max-Planck-Strasse 2, 37191 Katlenburg-Lindau, Germany.