New versus past silica crush curve experiments: application to Dimorphos benchmarking impact simulations

TL;DR

This paper reviews silica crush curve experiments, proposes a new power-law model for impact simulations, and demonstrates its improved accuracy over traditional quadratic models in asteroid impact scenarios.

Contribution

It introduces a universal power-law crush curve for silica, validated through benchmarking against impact simulations of asteroid Dimorphos.

Findings

The new crush curve better matches experimental data across pressure ranges.

Traditional quadratic models tend to underestimate or overestimate compression.

The proposed model is applicable universally to similar asteroid-like bodies.

Abstract

Crush curves are of fundamental importance to numerical modeling of small and porous astrophysical bodies. The empirical literature often measures them for silica grains, and different studies have used various methods, sizes, textures, and pressure conditions. Here we review past studies and supplement further experiments in order to develop a full and overarching understanding of the silica crush curve behavior. We suggest a new power-law function that can be used in impact simulations of analog materials similar to micro-granular silica. We perform a benchmarking study to compare this new crush curve to the parametric quadratic crush curve often used in other studies, based on the study case of the DART impact onto the asteroid Dimorphos. We find that the typical quadratic crush curve parameters do not closely follow the silica crushing experiments, and as a consequence they under (over) estimate compression close (far) from the impact site. The new crush curve presented here, applicable to pressures between a few hundred Pa and up to 1.1 GPa, might therefore be more precise. Additionally, it is not calibrated by case-specific parameters, and can be used universally for comet- or asteroid-like bodies, given an assumed composition similar to micro-granular silica.