<h2>AAS 99-158</h2>
<h2>Evaluation of the Dynamic Environment of an Asteroid                                                                                             </h2>
<h4>D.J. Scheeres, B.G. Williams, J.K. Miller                                                                                                                                           </h4>
Iowa State University, Ames, IA                                                                                                                                           
<h2> Abstract </h2>
This paper will present methods of analysis to quickly and systematically evaluate the dynamical environment close to an asteroid, concentrating mainly on the effect of the asteroid's gravity field and rotation state on the dynamical environment. Such an analysis is useful and needed for application to missions to small solar system bodies such as asteroids and comets where the true mass, gravity field, and rotation state will not be known until the spacecraft arrives at the body and these quantities are estimated. Generally, after these quantities have been estimated the complete mission profile must be re-designed in accordance with the actual values found at the asteroid. An integral part of this re-design will be the characterization of dynamics close to the body and the practical limits on how close the spacecraft can fly to the body before too large perturbations are experienced. Some specific applications to the NEAR  mission at Eros will be given.