Slow Biaxial Rotations of a Satellite in the Orbit Plane

The mode of a satellite attitude motion, named biaxial rotation in an orbit plane, is investigated. A satellite is supposed to be close to dynamic symmetric one. It rotates around its longitudinal axis, which in turn rotates around normal to the orbit plane; the angular rate of the longitudinal axis is greater by several fold the orbital mean motion, the deviation of that axis from the orbit plane is small. The investigation is based on numerical integration of the satellite attitude motion equations in which the gravitational and restoring aerodynamic torques as well as orbit evolution are taken into account. Biaxial rotations proved to be quite stable in a high orbit, and they was failed by the aerodynamic torque in low one. Satellite initial attitude and angular rates are found to provide the sufficiently long time of mode existence.