Technology for a robotic asteroid redirect mission

In-space transportation technology is the key to unlocking the material resources of near-Earth asteroids for the benefit of human spaceflight activities beyond low-Earth orbit. High-power solar electric propulsion, with power levels of around 50 kW represents the most capable, affordable, near-term propulsion technology available and is enabling for the capture and retrieval of entire small near-Earth asteroids. Future technology advances, stimulated by the successful retrieval of the first asteroid, will likely include scaling to higher power levels, operation at higher specific impulse levels, and ultimately the use of asteroid-derived materials as propellant.