1. Lunar and Planetary Institute; Houston Texas USA
2. Department of Terrestrial Magnetism; Carnegie Institution of Washington; Washington D.C. USA
3. NASA Goddard Flight Center; Greenbelt Maryland USA
4. Department of Earth, Atmospheric, and Planetary Sciences; Massachusetts Institute of Technology; Cambridge Massachusetts USA
5. Division of Geological and Planetary Sciences; California Institute of Technology; Pasadena California USA
6. Department of Earth and Planetary Sciences; Washington University; St. Louis Missouri USA
7. Department of Geological Sciences; Brown University; Providence Rhode Island USA