took one G. A. from Jupiter, one from Saturn, later from Uranus, and then move up to Neptune and beyond. Galileo passed by Venus then twice by Earth, and finally go up to its path Jupiter. Cassini passed by Venus twice, then Earth, and finally Jupiter on the way to Saturn [ 1 , 2 , 3 ].
In a gravity assist trajectory, angular momentum is transferred from the orbiting planet to a spacecraft, while the value of it’s speed relative to planet is not changed during a gravity assist flyby, but it’s direction is changed. However, both value and direction of spacecraft
evaluations regarding the masses and the distances of the participating bodies. In this way, a classic example in space dynamics is the Sun-Earth-Moon system.
Some important contributions related to the libration points in the restricted three-body problem with one or both primaries are oblate spheroids when the equatorial plane is coincident with the plane of motion were studied by Subbarao and Sharma [ 28 ], Sharma and Subbarao [ 23 ], and Markellos et al. [ 20 ]. Abouelmagd [ 9 ] also studied the effects of oblateness J 2 and J 4 for the more massive primary in the