Institute of Astronomy

Chaos and Predictability in Terrestrial Planet Formation Simulations

SpeakerTalk DateTalk Series
Volker Hoffmann28 July 2014Across HR 2014 Posters


The formation of terrestrial planets by the collisional growth of planetesimals is a stochastic process. We show that practically identical initial conditions result in a wide array of final planetary configurations. This highly chaotic behaviour questions the predictability of different scenarios for the formation and evolution of our solar system and planetary systems in general. We present two sets of numerical experiments that quantify this behaviour. Firstly, we demonstrate that simulations with slightly displaced particles are completely divergent after ~500 years, irrespective of initial displacement, particle number, and code accuracy. Secondly, we show final planetary configurations of initially similar simulations with and without giant planets after evolving them for 146 Myr. We find that the same simulations including giant planets tend to generate higher mass planets at lower semi-major axes than simulations without gas giants. This prediction can be tested with forthcoming observational programs.