1. Max Planck Institute for Solar System Research Goettingen Germany
2. Johns Hopkins University Applied Physics Laboratory Laurel MD USA
3. UCL Mullard Space Science Laboratory Dorking UK
4. The Centre for Planetary Sciences at UCL/Birkbeck London UK
5. Office of Space Research and TechnologyAcademy of Athens Athens Greece
6. NASA Goddard Space Flight Center Greenbelt MD USA