Planetesimals collisions: statistical properties of the ejecta
Abstract
The last stage of terrestrial planets formation is driven largely by collisions between planetesimals and planetary embryos. These collisions span a broad range of configurations, ranging from perfect merging of two colliding bodies to catastrophic collisions in which no major body survives and the entire mass is fragmented. While planetary collisions are well described by state of the art SPH simulations, the problem of including collisional fragments in N-body simulators is far from being solved. Several solutions have been proposed, the most sophisticated of which includes the effect of collisional ejecta by adding a few new bodies. In order to keep the total number of bodies in the simulation small, the fragments are all generated with the same mass, usually of the order of the mass of the Moon. Here we propose a new solution to this problem that consists of treating the fragments in a statistical way by including a localized potential in the N-body simulation that has the same effect of a cluster of fragments. The main properties of this potential were obtained by taking advantage of a catalog of SPH collisions, and by simulating systems containing both bodies and fragments through a hybrid symplectic integrator. We use this innovative formulation to study how the collision ejecta affect the formation and orbital evolution of terrestrial planets.
- Publication:
-
43rd COSPAR Scientific Assembly. Held 28 January - 4 February
- Pub Date:
- January 2021
- Bibcode:
- 2021cosp...43E.133C