Related papers: Stick-slip dynamics in penetration experiments on …
The dusty regolith covering the surfaces of asteroids and planetary satellites differs in size, shape, and composition from terrestrial soil particles and is subject to very different environmental conditions. Experimental studies of the…
Stick-slip motion, a common phenomenon observed during crawling of cells, is found to be strongly sensitive to the substrate stiffness. Stick-slip behaviours have previously been investigated typically using purely elastic substrates. For a…
We present a framework to study regolith segregation on rubble-pile asteroids (self-gravitating granular aggregates) due to seismic shaking induced by impacts sustained during their lifetimes. We first relate the amplitude and frequency of…
We present recent improvements in the simulation of regolith sampling processes in microgravity using the numerical particle method smooth particle hydrodynamics (SPH). We use an elastic-plastic soil constitutive model for large deformation…
Granular material that is bound by the low gravity of a small asteroid is mobilized by slow velocity impacts. These splashes generated by impacts might play an important role in sculpting the asteroid's surface. In laboratory experiments we…
In situ observations of small asteroids show that surfaces covered by boulders and coarse terrain are frequent on such bodies. Regolith grain sizes have distributions on approximately mm and cm scales, and the behavior of such large grains…
We studied the creep motion of granular materials in a gradient potential field that is created using a slow spin-up experiment device. Natural sand confined in the acrylic box is spun up by a controlled turntable and the surface flows are…
Despite their very low surface gravities, the surfaces of asteroids and comets are covered by granular materials - regolith - that can range from a fine dust to a gravel-like structure of varying depths. Understanding the dynamics of…
Understanding how stick-slip dynamics manifests in diverse physical conditions is a crucial topic in tribology. Although it has been extensively studied in simple frictional configurations, the characterization of stick-slip behavior in…
Seismic shaking is an attractive mechanism to explain the destabilisation of regolith slopes and the regolith migration found on the surfaces of asteroids (Richardson et al. 2004; Miyamoto et al. 2007). Here, we use a continuum mechanics…
Spin off events and impacts can eject boulders from an asteroid surface and rubble pile asteroids can accumulate from debris following a collision between large asteroids. These processes produce a population of gravitational bound objects…
Porosity is a key characteristic of the regolith on the surface of small bodies. The porosity of the regolith on the surface of asteroids is changed by applied pressure, and the relationship between pressure and porosity depends on the…
We discuss the results of simulations of an intruder pulled through a two-dimensional granular system by a spring, using a model designed to lend insight into the experimental findings described by Kozlowski et al. [Phys. Rev. E, 100,…
The regolith-covered surfaces of asteroids preserve records of geophysical processes that have occurred both at their surfaces and sometimes also in their interiors. As a result of the unique micro-gravity environment that these bodies…
This study is carried out in the framework of sample-return missions to asteroids that use a low-speed projectile as the primary component of its sampling mechanism (e.g., JAXA's Hayabusa and Hayabusa2 missions). We perform numerical…
In quasi-two-dimensional experiments with photoelastic particles confined to an annular region, an intruder constrained to move in a circular path halfway between the annular walls experiences stick-slip dynamics. We discuss the response of…
A loosely packed bed of sand sits precariously on the fence between mechanically stable and flowing states. This has especially strong implications for animals or vehicles needing to navigate sandy environments, which can sink and become…
Particle-particle and particle-gas processes significantly impact planetary precursors such as dust aggregates and planetesimals. We investigate gas permeability ($\kappa$) in 12 granular samples, mimicking planetesimal dust regoliths.…
In order to improve our understanding of landing on small bodies and of asteroid evolution, we use our novel drop tower facility to perform low-velocity (2-40 cm s^-1), shallow impact experiments of a 10 cm diameter aluminum sphere into…
The compression property of regolith reflects the strength and porosity of the regolith layer on small bodies and their variations in the layer that largely influence the collisional and thermal evolution of the bodies. We conducted…