Parametric resonance in oscillations of the spacecraft at effect of the variable aerodynamic moment

The motion of a spacecraft in a mode of gravitational stabilization when the double frequency of own oscillations is close to triple frequency of orbital motion is considered. Researches are carried in view of atmosphere density changes at spacecraft orbital motion and relation of the aerodynamic moment coefficient to orientation of spacecraft. On the basis of a method of averaging the technique of research of Hill's type equations solutions is constructed and main laws of spacecraft motion in a considered case are determined.