1. Geology Department University of Maryland College Park MD USA
2. Now at Jet Propulsion Laboratory California Institute of Technology Pasadena CA USA
3. College of Earth, Ocean, and Atmospheric Sciences Oregon State University Corvallis OR USA
4. Silicon Audio Inc. Pflugerville TX USA
5. Lunar and Planetary Laboratory University of Arizona Tucson AZ USA
6. Applied Physics Laboratory University of Washington Seattle WA USA
7. Department of Geosciences University of Alaska Fairbanks Fairbanks AK USA
8. NASA Marshall Space Flight Center Huntsville AL USA