[1] Observ Paris, LESIA, F-92195 Meudon, France
[2] Johns Hopkins Univ, Appl Phys Lab, Laurel, MD USA
[3] Univ Nice Sophia Antipolis, Observ Cote Azur, CNRS, Nice, France
[4] CALTECH, Jet Prop Lab, Pasadena, CA USA
[5] MIT, Cambridge, MA 02139 USA
[6] Univ London Imperial Coll Sci Technol & Med, London, England
[7] Max Planck Inst Solar Syst Res, Katlenburg Lindau, Germany
[8] INAF, Osservatorio Astrofis Arcetri, Florence, Italy
[9] Univ Alicante, E-03080 Alicante, Spain
[10] INAF, Inst Astrofis Spaziale & Fis Cosm, Rome, Italy
[11] INAF, Osservatorio Astron Roma, Monte Porzio Catone, Italy
[12] Queens Univ Belfast, Belfast, Antrim, North Ireland
[13] Open Univ, PSSRI, Milton Keynes MK7 6AA, Bucks, England
[14] CSIC, Inst Astrofis Andalucia, Granada, Spain
[15] Univ La Laguna, Inst Astrofis Canarias, Tenerife, Spain
[16] Univ La Laguna, Dep Astrofis, Tenerife, Spain
[17] CNRS, Ctr Rech Petrog & Geochim, Nancy, France
[18] Univ Helsinki, Helsinki, Finland
[19] FGI, Helsinki, Finland
[20] DLR, Berlin, Germany
[21] Museum Natl Hist Nat, F-75231 Paris, France
[22] Univ Tuscia, Viterbo, Italy
[23] CSIC, Inst Estudis Espacials Catalunya, Barcelona, Spain
[24] DLR RB MC, Cologne, Germany
[25] NASA, Lyndon B Johnson Space Ctr, Houston, TX 77058 USA