High altitude Sun-synchronous orbits as solutions of the circular restricted Sun-Earth-Moon-satellite 4-body problem

Abstract

The altitudes of the well-known Sun-Synchronous Orbits (SSOs) are limited to a few thousand kilometers. This is because the synchronousness is realized by the J2-term of the geopotential. In this study, as solutions of the circular restricted 4-body (Sun, Earth, Moon and satellite) problem, new SSOs at altitudes on the order of magnitude of a million kilometers are reported. Lunar gravity assist plays an important role. Symmetries in the system are utilized to ease the numerical process. Besides the scientific interest, the result could be practical for reducing the variation of the heat input from the earth to satellites.