Temporarily captured asteroids as a pathway to affordable asteroid retrieval missions

The population of "temporarily captured asteroids" offers attractive candidates for asteroid retrieval missions. Once naturally captured, these asteroids have lifetimes ranging from a few months up to several years in the vicinity of the Earth. One could potentially extend the duration of such temporary capture phases by acting upon the asteroid with slow deflection techniques that conveniently modify their trajectories, allowing for an affordable access and in situ study. In this paper, a case study on asteroid 2006 RH120 is presented, which was temporarily captured during 2006-2007 and is the single known member of this category to date. Simulations estimate that deflecting the asteroid with 0.27N for less than six months and a change of velocity, V of barely 32m/s would have sufficed to extend the capture for over five additional years. The study is extended to another nine virtual asteroids, showing that low-V (less than 15m/s) and low-thrust (less than 1N) deflections initiated a few years in advance may extend their capture phase for several years, and even decades.