1. Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, USA.
2. Department of Earth and Planetary Sciences, The University of Tennessee, Knoxville, Tennessee, USA.
3. SETI Institute/NASA Ames Research Center, Moffett Field, California, USA.
4. The Robotics Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA.
5. Department of Geosciences, University of Montana, Missoula, Montana, USA.