Impact excitation of a seismic pulse and vibrational normal modes on asteroid Bennu and associated slumping of regolith

•In small asteroids, rare energetic impactors can excite seismic waves with frequencies near those of the asteroid’s slowest normal modes. The distribution of seismic reverberation is not evenly distributed.•With mass-spring model elastic simulations, we model excitation of seismic waves on asteroids with different shapes. The simulations exhibit antipodal focusing and normal mode excitation.•Seismic reverberation on asteroid Bennu could have raised the height of its equatorial ridge by a few meters and raised a peak on near the impact’s antipode.