Related papers: Dropping the Ball: The effect of anisotropic granu…
We measure ejecta mass as a function of azimuthal and impact angle for 104 m/s oblique impacts into sand. We find that the ejecta mass distribution is strongly sensitive to azimuthal angle with as high as 8 times more mass in ejecta on the…
Drop impact experiments allow the modelling of a wide variety of natural processes, from raindrop impacts to planetary impact craters. In particular, interpreting the consequences of planetary impacts requires an accurate description of the…
Several physical mechanisms are involved in excavating granular materials beneath a vertical jet of gas. These occur, for example, beneath the exhaust plume of a rocket landing on the soil of the Moon or Mars. A series of experiments and…
Combining high-speed photography with laser profilometry, we study the dynamics and the morphology of liquid-drop impact cratering in wet granular media---a ubiquitous phenomenon relevant to many important geological, agricultural, and…
We consider how an impact generated seismic pulse affects the surface of an asteroid distant from the impact site. With laboratory experiments on dry polydisperse gravel mixtures, we track the trajectories of particles ejected from the…
Our earlier laboratory measurements showed that low-velocity sand impacts release fine <5 {\mu}m dust from a Martian simulant soil. This dust will become airborne in the Martian atmosphere. Here, we extend this study by measuring…
Impact of a solid object onto a small-body surface can be modeled by the solid impact onto a hierarchically structured granular target. Impact drag force model for the hierarchically structured granular target is developed based on the…
NASA's Double Asteroid Redirection Test (DART) mission will impact its target asteroid, Dimorphos, at an oblique angle that will not be known prior to the impact. We computed iSALE-3D simulations of DART-like impacts on asteroid surfaces at…
Sudden release of energy in explosion creates craters in granular media. In comparison with well-studied impact cratering in granular media, our understanding of explosion cratering is still primitive. Here, we study low-energy lab-scale…
The impact of droplets on liquid pools is ubiquitous in nature and many industrial applications. Most previous studies of droplet impact focus on Newtonian fluids, while less attention has been paid to the impact dynamics of non-Newtonian…
We investigate the roles of spin and packing fraction on the dynamics of cratering when a solid projectile impacts a granular bed at different incident angles. For that, we carried out DEM (discrete element method) computations in which we…
From small seeds falling from trees to asteroids colliding with planets and moons, the impact of projectiles onto granular targets occurs in nature at different scales. In this paper, we investigate open questions in the mechanics of…
Experiments on the low-speed impact of solid objects into granular media have been used both to mimic geophysical events and to probe the unusual nature of the granular state of matter. Observations have been interpreted in terms of…
An understanding of the post-impact dynamics of ejecta clouds are crucial to the planning of a kinetic impact mission to an asteroid, and also has great implications for the history of planetary formation. The purpose of this article to…
We examine ejecta generated by ultra low velocity impacts under asteroid conditions. In an environment of precisely controlled milligravity and under vacuum, impacts with velocities in the range of centimeters/second are performed with…
The dynamics, velocity fluctuations, and particle-plate interactions for a 2D granular gas of shaken, non-spherical particles are studied experimentally. The experiment consists of a horizontal plate that is vertically oscillated to drive…
Recently published crater statistics on the small asteroids 25143 Itokawa and 433 Eros show a significant depletion of craters below approx. 100 m in diameter. Possible mechanisms that were brought up to explain this lack of craters were…
We study drop impacts on immiscible viscous liquid pool and investigate the formation of droplet surface craters using experimental and theoretical analysis. We attribute the formation of air craters to the rapid deceleration of the droplet…
We study the influence of particle shape anisotropy on the occurrence of avalanches in sheared granular media. We use molecular dynamic simulations to calculate the relative movement of two tectonic plates. % with transform boundaries. Our…
An incident fast ion in the electronic stopping regime produces a track of excitations which can lead to particle ejection and cratering. Molecular Dynamics simulations of the evolution of the deposited energy were used to study the…