  Near-Earth small-body mission targets 162173 Ryugu, 101955 Bennu, and 25143
Itokawa produce gravity fields around 4 orders of magnitude below that of Earth
and their irregular shapes, combined with rotational effects produce varying
surface potentials. Still, we observe familiar geologic textures and landforms
that are the result of the granular physical processes that take place on their
surfaces. The nature of these landforms, however, their origins, and how these
surfaces react to interrogation by probes, landers, rovers, and penetrators,
remain largely unknown, and therefore landing on an asteroid and manipulating
its surface material remains a daunting challenge. The AOSAT+ design is a 12U
CubeSat that will be in Low-Earth Orbit (LEO) and that will operate as a
spinning on-orbit centrifuge. Part of this 12U CubeSat will contain a
laboratory that will recreate asteroid surface conditions using crushed
meteorite as a regolith proxy. The spinning of the laboratory will simulate the
surface gravity of asteroids 2 km and smaller. The result is a bed of realistic
regolith, the environment that landers and diggers and maybe astronauts will
interact with. A crucial component of this mission involves the reproduction of
the experimental results in numerical simulation in order to extract the
material parameters of the regolith and its behavior in a sustained, very low
but nonzero-gravity environment.
