Asteroid Regolith Mechanics and Primary Accretion Experiments in a Cubesat

Access to stable, long-duration microgravity environments for asteroid regolith experiments, rubble pile asteroid research, small body lander, sampler studies, basic examinations of planetesimal accretion and evolution need not be expensive. On the one hand, billion-dollar concepts of returning entire ~3-5 m asteroids [1] are being considered that would ‘nab’ an asteroid to cislunar space [2], where detailed investigations could be conducted at a relaxed pace by astronauts onboard a space station. A much cheaper and more immediate alternative is to pack a few kg of fine fragments of common meteorite into a cubesat, using it to build a ‘patch of asteroid’ inside two experimental chambers onboard a spun-up 3U cubesat. We show that our design (AOSAT, Fig. 1) can mimic the asteroid surface environment in sufficient detail, provideng us with a low cost orbiting laboratory for asteroid and primary accretion research. Design: Two 1U chambers containing meteorite fragments and dust are on either side of a central chamber containing the spacecraft itself (Figure 1). For zero-gravity research (primary accretion) the spaceraft is stabilized to zero rotation by a magnetorquer (see below). For microgravity research, the spacecraft is spun on its minor axis using a flywheel, until the rocks are accelerated to the walls in simulated microgravity. We show that this approach is suitable, in terms of being a good approximation, and further can be achieved at very low cost, well under $1M. Scientific Motivations. Zero-G experiments are common, using drop towers and parabolic flights, but in addition to any operational obstacles they are intrinsically limited to durations that are short compared