Earth-Crossing Asteroids Deflection with a Sailcraft

Abstract

Fast intercept trajectories are discussed to impact the dangerous Earth-crossing asteroids by using a solar sail spacecraft for the near to far-term missions. The heliocentric trajectory with a single solar photonic assist is considered to transfer the sail kinetic impactor from the Earth orbit to the collision point with the asteroid. Two options of such trajectories, i.e., the direct flyby and the angular momentum reversal trajectory, are compared via numerical simulations with respect to the transfer time and the relative collision velocity to determine which one is more suitable. The variation trend of the relative collision velocities are presented for different mission scenarios as a function of the sail lightness number. For a square flat ideally reflective sail with a given assembly loading, the determination of the impactor mass is studied to obtain the highest value of the net increment velocity of the asteroid.