In-situ Formation of Mars-like Planets - Results from Hundreds of N-body Simulations That Include Collisional Fragmentaion
Abstract
Dynamical simulations of the formation of the Solar System have been successful at reproducing the broad characteristics of the terrestrial planets, however they have consistently struggled to reproduce the small mass of Mars within the timescale provided by geochemical constraints. This has prompted the development of new models that invoke various mechanisms, such as giant planet migration, that result in the formation a small Mars. Due primarily to the computationally intensive nature of these models, most previous studies were based on a small (less than a dozen) number of simulations and did not include the effects of collisional fragmentation. However, these systems are highly stochastic and require a large number of simulations in order to infer the results in a statistical manner. Here we show that by performing 150 N-body simulations of terrestrial planet formation around the Sun that include collisional fragmentation, the formation of Mars-analogs is a natural outcome, albeit not a common one. Approximately 13% of the simulations produced a Mars-sized planet near Mars’ current orbit that accreted at least 90% of its mass within 3 Myr. The current architecture of the planets in our Solar System can be thought of as one draw from a distribution of planetary systems that can form from essentially the same protoplanetary disk. These results support the idea that Mars may essentially be a stranded embryo that survived the giant impact phase without a significant amount of accretion or erosion, but that it need not be the only outcome from the chaotic process of forming planets.
- Publication:
-
AAS/Division for Planetary Sciences Meeting Abstracts #47
- Pub Date:
- November 2015
- Bibcode:
- 2015DPS....4750706B