Pendulum Motions of a Spacecraft Equipped with a Solar Sail and Tethered to a Heliocentric Space Station

Motions of a spacecraft equipped with a solar sail and tethered to a heliocentric station is considered. The problems of the spacecraft motion along plane sections of a sphere, restricting its motion with respect to the station, are studied as analogs of perturbed librations of a spherical pendulum or as some generalizations of them.