Construction and simulated drop of a sintered two-meter-sized boulder made up of a 2:1 dust–ice mixture (34 000 computational parcels) from 30 m above the surface (beige-colored plane) of comet 67P. Oblique impact with impact speed of 0.1 m s⁻¹ and impact angle of 30° measured from the normal to the surface. Top row: construction of the boulder. (a) Loose filling of a large sphere with noncontacting randomly sized and positioned dust (gray spheres) and ice (blue spheres) particles. (b) Compaction of the boulder to the bulk mass density and porosity of comet 67P. (c) Removal of particles outside the intended boulder diameter and formation of sinter bonds (thick red bars) between ice particles. Bottom row: (d–f) Several stages after impacting the surface of 67P; sinter bond representation is omitted for clarity. Lighter shades of gray or blue visualize a higher topography. In case (c), the material is visualized partly transparent.