Forced motions around triangular libration points by solar radiation pressure in a binary asteroid system

Abstract

By using two tri-axial ellipsoids to approximate the two asteroids, forced orbits around triangular libration points of the binary asteroid system (BAS) induced by solar radiation pressure are studied. The work is firstly carried out in the doubly synchronous binary asteroid system (DSBAS). The results show that the amplitude of the forced periodic orbit can be large, even for small to moderate surface area-to-mass ratios of the spacecraft. The position, amplitude, and stability of these forced periodic orbits are influenced by the asteroids' non-spherical terms. Also, the stability of them may be different, depending on the Sun's motion direction w.r.t. to the BAS's orbit motion direction. This study is then generalized to the asynchronous and synchronous BAS (ABAS and SBAS, respectively). The forced orbits in the complete system are quasi-periodic orbits around the forced periodic orbit of the averaged system.