Asteroid retrieval feasibility

This paper describes the interim results of a study sponsored by the Keck Institute for Space Studies to investigate the feasibility of identifying, robotically capturing, and returning an entire Near-Earth Asteroid (NEA) to the vicinity of the Earth by the middle of the next decade. The feasibility hinges on finding an overlap between the smallest NEAs that can be reasonably discovered and characterized and the largest NEAs that can be captured and transported in a reasonable flight time. This overlap appears to be centered on NEAs with a nominal diameter of roughly 7 m corresponding to masses in the range of 250,000 kg to 1,000,000 kg. Trajectory analysis based on asteroid 2008HU4 suggests that such an asteroid could be returned to a high-Earth orbit using a single Atlas V-class launch vehicle and a 40-kW solar electric propulsion system by 2026. The return of such an object could serve as a testbed for human operations in the vicinity of an asteroid. It would provide a wealth of scientific and engineering information and would enable detailed evaluation of its resource potential, determination of its internal structure and other aspects important for planetary defense activities.