Flight dynamics over irregular asteroids

Asteroid explorations have been one of the focuses in deep space explorations as well as of great signiflcance. Due to irregular shapes of most asteroids, dynamical behaviors of spacecraft close to asteroids are very complicated. The spacecraft is easy to impact the body's surface or escape subject to the non-spherical gravitational attracting coupled with the fast rotating, as well as the solar radiation pressure force. Recent research progress and modeling methods of irregular asteroids are briefly introduced. Dynamical characteristics in irregular gravitational flelds are presented in detail for reference of new directions, including equilibrium points, local manifolds, natural periodic orbits and body-flxed hovering flights.