The dynamic strength of an ordinary chondrite

Abstract

Abstract– Dynamic and quasistatic unconfined compression experiments were performed on samples of the L5 ordinary chondrite MacAlpine Hills (MAC) 88118. The dynamic compressive strength measurements are the first of its kind for a stony meteorite, and indicate that the material tested here exhibits significant increase in compressive strength with increasing strain rate. This increase in compressive strength is larger than the increases typically observed in terrestrial rock specimens compressed over a similar range of strain rates. The details of the failure process are investigated by recording images of the experiments in real time. Specifically, the crack growth speeds in the dynamic compression experiments are measured from ultrahigh‐speed images. These speeds are significantly lower than the speeds observed in terrestrial analogs that are typically used in numerical investigations of large‐scale impacts. The implications of these measurements of strength and failure process are explored in the contexts of atmospheric disruption of meteors and impact cratering/disruption of asteroids.