Outgoing-to-incoming speed ratio of the lander as a function of the impact angle (0° is a normal impact, and larger angles correspond to more grazing impacts), the material friction, and the position of the boulder for a 30 cm bed. The line types represent the frictional properties of the granular bed, and the symbols and colors represent the different boulder positions, as indicated at the bottom. MASCOT lands on its back corner first in these simulations. Stochasticity due to computational noise could lead to changes in the speed ratio of up to 0.1.