ABSTRACT
The motion of the spacecraft in the solar system is controlled by various physical forces. These are the gravitational forces exerted by the sun and natural celestial bodies in the solar system: environmental forces; and the jet power of the spacecraft's engines. Different methods and approaches which have been developed to analyze gravity assist maneuvers allow the factors forming the flyby trajectory to be taken into account to a different extent. Gravity assist maneuvers can be used in interplanetary missions to reach distant planets, in flights between planets of the Earth's group, and in missions with the spacecraft returning to Earth. The accepted model of perturbation maneuvering, in which the gravisphere of the flyby body is assumed to have zero radius, makes it easier to assess the perturbation effect of a planet on the characteristics of spacecraft post-perturbation orbit.
