1. Hawaii Institute of Geophysics and Planetology; School of Ocean and Earth Science and Technology; University of Hawaii at Mānoa; Honolulu Hawaii 96822 USA
2. Museu Nacional/UFRJ; Quinta da Boa Vista-RJ; Rio de Janeiro CEP 20.940-040 Brazil
3. Planetary and Space Sciences; The Open University; Walton Hall Milton Keynes MK7 6AA UK
4. Departments of Earth and Space Sciences and Chemistry and Biochemistry; Institute of Geophysics and Planetary Physics; University of California; Los Angeles California 90095-1567 USA
5. Space Sciences Laboratory; University of California; Berkeley California 94720-7450 USA
6. Department of Physics; Purdue University; West Lafayette Indiana 47907-2036 USA
7. Space Science and Astrobiology Division; NASA Ames Research Center; MS 245-3 Moffett Field Mountain View California 94035 USA
8. Department of Earth Sciences; ETH Zürich; NW C 82 Zürich CH-8092 Switzerland
9. Centro Brasileiro de Pesquisas Físicas; Rua Dr. Xavier Sigaud 150 Rio de Janeiro 22290-180 Brazil
10. CEREGE UM 34; CNRS/Aix-Marseille University; Aix-en-Provence 13545 France
11. IPGP; Paris France
12. Laboratori Nazionali del Gran Sasso; Istituto Nazionale di Fisica Nucleare; Via G. Acitelli 22 Assergi (AQ) I-67100 Italy
13. Departamento de Geologia; UFRJ; Av. Athos da Silveira Ramos 274. Cidade Universitária Rio de Janeiro Brazil
14. Department of Environmental Sciences (DES); Helmholtz Zentrum München; Ingolstädter Landstrasse 1 Neuherberg 85764 Germany
15. R. Francisco Ricci; 181 33D Vila Ema São José dos Campos/SP São Paulo CEP 12.243-261 Brazil