A Model of Orbiting Spacecraft Motion near Cometary Nucleus. Part I

The first part of a model of orbiting spacecraft motion near a cometary nucleus is given in the Paper. The sun gravitation, solar light pressure and the cometary nucleus attraction are considered. The model provides two options of the nuclears rotation: both uniaxial rotation and biaxial rotation with a nutation angle and precession of the eigen-rotation axis. The nucleus is approximated by the homogeneous prolate spheroid with possible mascons on its surface.