TERRESTRIAL PLANET FORMATION IN A PROTOPLANETARY DISK WITH A LOCAL MASS DEPLETION: A SUCCESSFUL SCENARIO FOR THE FORMATION OF MARS

Autor(es)

Izidoro, A. ^{[1, 2, 3]} ; Haghighipour, N. ^{[4, 5, 6]} ; Winter, O. C. ^[1] ; Tsuchida, M. ^[7]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista, UNESP, Grp Dinamica Orbital & Planetol Guaratin, BR-12516410 Sao Paulo - Brazil

^[2] Capes Fdn, Minist Educ Brazil, BR-70040020 Brasilia, DF - Brazil

^[3] Univ Nice Sophia Antipolis, CNRS, Observ Cote Azur, Lab Lagrange, F-06304 Nice 4 - France

^[4] Univ Hawaii Manoa, Inst Astron, Honolulu, HI 96822 - USA

^[5] Univ Hawaii Manoa, NASA Astrobiol Inst, Honolulu, HI 96822 - USA

^[6] Univ Tubingen, Inst Astron & Astrophys, D-72076 Tubingen - Germany

^[7] Univ Estadual Paulista, UNESP, DCCE IBILCE Sao Jos Rio Preto, BR-15054000 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ASTROPHYSICAL JOURNAL; v. 782, n. 1 FEB 10 2014.
• Citações Web of Science: 40

Resumo

Models of terrestrial planet formation for our solar system have been successful in producing planets with masses and orbits similar to those of Venus and Earth. However, these models have generally failed to produce Mars-sized objects around 1.5 AU. The body that is usually formed around Mars' semimajor axis is, in general, much more massive than Mars. Only when Jupiter and Saturn are assumed to have initially very eccentric orbits (e similar to 0.1), which seems fairly unlikely for the solar system, or alternately, if the protoplanetary disk is truncated at 1.0 AU, simulations have been able to produce Mars-like bodies in the correct location. In this paper, we examine an alternative scenario for the formation of Mars in which a local depletion in the density of the protosolar nebula results in a non-uniform formation of planetary embryos and ultimately the formation ofMars-sized planets around 1.5 AU. We have carried out extensive numerical simulations of the formation of terrestrial planets in such a disk for different scales of the local density depletion, and for different orbital configurations of the giant planets. Our simulations point to the possibility of the formation of Mars-sized bodies around 1.5 AU, specifically when the scale of the disk local mass-depletion is moderately high (50%-75%) and Jupiter and Saturn are initially in their current orbits. In these systems, Mars-analogs are formed from the protoplanetary materials that originate in the regions of disk interior or exterior to the local mass-depletion. Results also indicate that Earth-sized planets can form around 1 AU with a substantial amount of water accreted via primitive water-rich planetesimals and planetary embryos. We present the results of our study and discuss their implications for the formation of terrestrial planets in our solar system. (AU)

• Processo FAPESP: 11/08171-3 - Dinâmica orbital de pequenos corpos
• Beneficiário: Othon Cabo Winter
• Modalidade de apoio: Auxílio à Pesquisa - Temático