Numerical modeling of asteroid survivability and possible scenarios for the Morokweng crater-forming impact

摘要

The fate of the impactor is an important aspect of the impact-cratering process. Defining impactor material as surviving if it remains solid (i.e., does not melt or vaporize) during crater formation, previous numerical modeling and experiments have shown that survivability decreases with increasing impact velocity, impact angle (with respect to the horizontal), and target density. Here, we show that in addition to these, impactor survivability depends on the porosity and shape of the impactor. Increasing impactor porosity decreases impactor survivability, while prolate-shaped (polar axis>equatorial axis) impactors survive impact more so than spherical and oblate-shaped (polar axis