1. Institut für Geophysik und Extraterrestrische Physik Technische Universität Braunschweig Braunschweig Germany
2. Johns Hopkins University Applied Physics Laboratory Laurel MD USA
3. Department of Earth, Planetary, and Space Sciences University of California Los Angeles CA USA
4. Department of Physics Imperial College London London UK
5. Space Research Institute Austrian Academy of Sciences Graz Austria
6. NASA Goddard Space Flight Center Greenbelt MD USA