1. INAF-Istituto di Astrofisica e Planetologia Spaziali; Rome Italy
2. CNR-Istituto di Scienze dell'Atmosfera e del Clima; Bologna Italy
3. Dipartimento di Fisica e Astronomia; Università di Bologna; Bologna Italy
4. Laboratoire de Physique Atmosphérique et Planétaire; Université de Liège; Liège Belgium
5. Space Science and Engineering Division; Southwest Research Institute; San Antonio Texas USA
6. NASA Goddard Space Flight Center; Greenbelt Maryland USA
7. Planetary Science Laboratory; University of Michigan; Ann Arbor Michigan USA
8. Laboratory for Atmospheric and Space Physics; University of Colorado Boulder; Boulder Colorado USA
9. Planetary Science Institute; Tucson Arizona USA
10. Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
11. Department of Physics and Astronomy; University of Iowa; Iowa City Iowa USA
12. The Johns Hopkins University Applied Physics Laboratory; Laurel Maryland USA
13. Plasma Physics Laboratory; Princeton University; Princeton New Jersey USA
14. Departamento de Fisica; Universidad de Atacama; Copiapò Chile
15. Agenzia Spaziale Italiana; Rome Italy