1. National Observatory , Rio de Janeiro, RJ 20921-400, Brazil
2. Grupo de Dinâmica orbital e Planetologia, São Paulo State University , Guaratinguetá, SP 12516-410, Brazil
3. Department of Earth, Environmental and Planetary Sciences , 6100 MS 126, Rice University, Houston, TX 77005, USA
4. Department of Physics and Astronomy 6100 MS 550, Rice University , Houston, TX 77005, USA
5. São Paulo State University , Guaratinguetá, SP 12516-410, Brazil
6. Centro Federal de Educação Tecnológica de Minas Gerais - CEFET , Curvelo, MG 35790-000, Brazil