A Comparison of Crater-Size Scaling and Ejection-Speed Scaling During Experimental Impacts in Sand

Abstract

Nondimensional scaling relationships are used to understand various cratering processes including final crater sizes and the excavation of material from a growing crater. The principal assumption behind these scaling relationships is that these processes depend on a combination of the projectile's characteristics, namely its diameter, density, and impact speed. This simplifies the impact event into a single pointsource. So long as the process of interest is beyond a few projectile radii from the impact point, the pointsource assumption holds. These assumptions can be tested through laboratory experiments in which the initial conditions of the impact are controlled and resulting processes measured directly. In this contribution, we continue our exploration of the congruence between cratersize scaling and ejectionspeed scaling relationships. In particular, we examine a series of experimental suites in which the projectile diameter and average grain size of the target are varied