Natural landing dynamics near the secondary in single-tidal-locked binary asteroids

The hopping dynamics of a lander in single-tidal-locked binary asteroid systems is explored. A coupled orbit-attitude dynamical model of the lander in the body-fixed frame of the secondary is established by considering the non-spherical perturbations from the two bodies. As an approximate model, the binary system is treated as an oblate spheroid-ellipsoid system. Lander deployment to the secondary is numerically simulated to examine the motion characteristics by varying the primary mass and system period. Two dynamical parameters related to the characteristic properties of the binary system are introduced to reveal the intrinsic reasons for different landing trajectory evolutions. These two dynamical parameters can effectively provide a measure to estimate the hopping evolution in different binary systems.