1. Office of Space Research and TechnologyAcademy of Athens Athens Greece
2. Institute of Astronomy, Astrophysics, Space Applications and Remote SensingNational Observatory of Athens Athens Greece
3. School of Physics and AstronomyUniversity of Southampton Southampton UK
4. Planetary Science Institute Tucson Arizona USA
5. Applied Physics LaboratoryThe Johns Hopkins University Laurel Maryland USA
6. Department of PhysicsUniversity of Maryland College Park Maryland USA
7. Blackett LaboratoryImperial College London London UK
8. Max Planck Institute for Solar System Research Goettingen Germany
9. Laboratory for Atmospheric and Space PhysicsUniversity of Colorado Boulder Boulder Colorado USA