Motion analysis of spacecraft around the asteroid Ivar

The asteroid Ivar is modeled as a tri-axial ellipsoid, its sphere gravitational potential is given, and spacecraft orbital dynamics equation around the asteroid Ivar is established. According to integral Jacobi constant, the spacecraft zero-velocity curves in the vicinity of asteroid is described and feasible motion regime is analyzed. Limited condition and periapsis radius corresponding to difference eccentricity against impact surface of the asteroid Ivar is presented. Effect of asteroid oblateness and ellipticity to orbital stability is analyzed. The math simulation indicate that orbit energy, angular momentum, periapsis radii and eccentricity of direct orbit experience much large changes in a orbit periods, by contraries, correspond parameter of retrograde orbits changes little.