Meteoroid Impact Detection for Exploration of Asteroids: Small Satellites for Asteroid Characterization

Abstract

The Meteoroid Impact Detection for Exploration of Asteroids concept addresses the challenge of characterizing an asteroid surface using a small satellite with a constellation of free-flying plasma sensors. The sensors detect ions ejected from the surface of an asteroid by meteoroid impacts, enabling the surface composition to be inferred. This paper presents an overview of this concept and focuses on establishing the feasibility of the measurement technique. Through an energy approach, it is found that the ejecta plume geometry depends strongly on the size of the meteoroid and that the plasma produced by nanogram-sized impactors expands in a nearly hemispherical plume, which is capable of being detected by a small number of free-flying plasma sensors in proximity to the asteroid surface. Using the Meteoroid Engineering Model, it is shown that the rate of detectable meteoroid impacts on near-Earth asteroids is approximately , which is sufficient to support a short-duration mission. A preliminary study on the requirements of the spacecraft indicates that this mission concept can be achievable using a 10–20 kg spacecraft, which would enable widespread exploration of near-Earth asteroids at a low cost.