Dust N-body simulations and their implications to formation of small Solar System bodies
speaker: Misako Tatsuuma
Abstract:
Small bodies in the Solar System, such as comets and asteroids, are thought to be leftover planetesimals or rubble piles, which are accumulations of collisional debris of planetesimals. However, the formation process of these small bodies is not fully understood. To constrain it by using the bulk densities of observed small bodies in the Solar System, we measured compressive strength of dust aggregates by using dust adhesion N-body simulation, calculated their diameters and bulk densities, which are determined by balancing the compressive strength with the self-gravity, and compared them with observation results of small bodies. We found that comets can be explained by direct coagulation in terms of internal density, but it requires fragile material. On the other hand, we found that asteroids are too dense to be explained by direct coagulation. To explain the bulk densities of asteroids, we need compression in large parent bodies, which implies that asteroids are rubble piles.