A closed-form solution for the three-body problem and a Sun-Earth-Moon orbit solution

Abstract The study of the motions of planets, satellites, and other celestial bodies is one of the important problems in basic physics and astronomy. The solution to the two-body problem enables astronomers to predict the orbits of the Moon, satellites, and spaceships around the Earth. The general analytic solution for the three-body problem stands unsolved except in some special cases, such as the Sun-Earth-Moon problem, in which the mass of the Moon is neglected. This reduces the problem to a two-body problem. In this work, the author presents a general solution to the problem in a closed form in terms of two basic particle-particle vectors. The position vector of each particle is expressed in terms of the centre of mass and the two basic particle-particle vectors. This solution is used for studying the three-body problem with gravitational interaction without imposing the non-zero-total angular-momentum condition or ignoring any masses. The Sun-Earth-Moon problem was solved in the general case and showed an expected orbital motion with a perturbation in the Earth-Sun orbit due to the revolution of the Moon. This solution is the key to future studies for n-body problem solutions.