Institution: | 1. Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91106, USA;2. Department of Physics, University of Wisconsin, Madison, WI 53706, USA;3. NASA Goddard Space Flight Center, Greenbelt, MD 20706, USA;4. Space Science Center, University of New Hampshire, Durham, NH 03824, USA;5. Department of Astronomy, University of Wisconsin, Madison, WI 53706, USA |