Impact experiments of porous targets

Abstract

Porous structure is common in the asteroids and satellites of the outer planets. It is important to study the relationship between the structure of small bodies and their thermal and collisional evolution. Our previous study showed that high velocity impacts need higher specific energy than low velocity impacts for catastrophic disruption when the targets have same compressive strength (Setoh et al. 2006). This is probably due to the difference in the degree of attenuation of the stress wave in the tar-gets. In order to investigate the attenuation rate of the stress wave in the porous targets, we measured the fragment velocities of each targets.