The influence of the sphericity of the Earth’s surface on the orientation control of the earth remote sensing spacecraft

The article considers a method of reorientation of a space remote sensing apparatus of the Earth moving in a circular orbit using flywheel engines. In this case, the influence of the gravitational moment is taken into account, and the movement is considered at the time interval when the object of observation is in the line of sight of the spacecraft. In the course of the research, geometric dependences of the angles of nutation and precession on time were derived, the object's field of view was determined, differential equations of motion of the spacecraft relative to the center of mass were constructed and their solutions were obtained. The obtained dependences make it possible to evaluate the influence of the inertial mass characteristics of the system and the initial conditions on the motion control of the spacecraft. The dependences of the moments controlling the rotation of the rotors on time are constructed, which made it possible to estimate the parameters of the engines necessary for these purposes. The article presents the results of the conducted studies showing the operability of the developed mathematical model. A practical application may be the use of the results obtained when aiming spacecraft at an object of observation.