Asteroid body-fixed hovering using nonideal solar sails

The problem of body-fixed hovering over an asteroid using a compact form of nonideal solar sails with a controllable area is investigated. Nonlinear dynamic equations describing the hovering problem are constructed for a spherically symmet- ric asteroid. Numerical solutions of the feasible region for body-fixed hovering are obtained. Different sail models, including the cases of ideal, optical, parametric and solar photon thrust, on the feasible region is studied through numerical simulations. The influence of the asteroid spinning rate and the sail area-to-mass ratio on the feasi- ble region is discussed. The required orientations for the sail and their corresponding variable lightness numbers are given for different hovering radii to identify the feasible region of the body-fixed hovering. An attractive scenario for a mission is introduced to take advantage of solar sail hovering.