Dr. Daniel D. Durda
(SwRI/NASA Headquarters)

University of Florida Astronomy Colloquium - Oct. 17th, 2007

Breaking Up Is Easy To Do: Numerical Models and Laboratory Experiments on Impact Disruption of Asteroids and Meteorites

We have been investigating the properties of satellites and the morphology of size frequency distributions (SFDs) resulting from a suite of 160 SPH/N-body simulations of impacts into 100-km diameter solid basalt parent asteroids. Our simulations utilize a 3-dimensional smooth-particle hydrodynamics (SPH) code to model the impact between the colliding asteroids. The outcomes of the SPH models are handed off as the initial conditions for N-body simulations, which follow the trajectories of the ejecta fragments to search for the formation of satellite systems. Our results show that catastrophic and large-scale cratering collisions create numerous binary systems matching the properties of observed main-belt asteroid satellites.

Laboratory-scale impact experiments can provide direct knowledge of the size distribution of dust-size debris produced directly from the impact disruption of ~5-cm scale meteorite targets, roughly the size scale of the immediate parent bodies of zodiacal dust particles. I will also report results from a set of impact disruption experiments involving chondritic meteorite samples, conducted at the NASA Ames Vertical Gun Range (AVGR).