Introduction: We have used the Ansys Inc. AUTODYN ® software [1] to hydrodynamically model small particle impacts into aluminium (Al) foil, under the conditions of the Stardust encounter with comet 81P/Wild 2 [2] (i.e., normal incidence, 6 km s -1 ). We compare results of impact models, based on carefully defined particle structures, with three-dimensional (3D) crater shapes reported from Stard...