Near Earth Object Orbit Modification Using Gravitational Coupling

It has been well documented that the population of near Earth objects (NEO) poses a terrestrial impact hazard [1-4]. Although current efforts are focused on detecting and cataloging such objects, various schemes for hazard mitigation have been proposed and investigated in some detail [5-15]. Nuclear devices appear attractive for deflecting potentially hazardous NEOs [5], although serious political issues arise concerning the deployment of such devices in space [11]. To overcome such difficulties, a range of nonnuclear options have been proposed. Concepts include focusing solar radiation onto the target asteroid with a large collector and smaller steerable secondary mirror to generate a hot jet of exhaust gas [6,7] or coating the asteroid to alter its albedo, and hence modify the Yarkovsky induced acceleration [8]. Somewhat more conventional approaches center on the use of kinetic energy impacts from either prograde [12,13] or retrograde orbits [9,10], or the use of continuous low thrust to increase the predicted Earth miss distance of the NEO using large solar or nuclear electric vehicles.