The paper studies the nonlinear dynamics of a flexible tethered satellite system subject to space environments,such as the J_2perturbation,the air drag force,the solar pressure,the heating effect,and the orbital eccentricity.The flexible tether is modeled as a series of lumped masses and viscoelastic dampers so that a finite multidegree-of-freedom nonlinear system is obtained.The stability of equilibrium positions of the nonlinear system is then analyzed via a simplified two-degree-freedom model in an orbital reference frame.In-plane motions of the tethered satellite system are studied numerically,taking the space environments into account.A large number of numerical simulations show that the flexible tethered satellite system displays nonlinear dynamic characteristics,such as bifurcations,quasi-periodic oscillations,and chaotic motions. The paper studies the nonlinear dynamics of a flexible tethered satellite system subject to space environments, such as the J_2perturbation, the air drag force, the solar pressure, the heating effect, and the orbital eccentricity. The flexible tether is modeled as a series of lumped masses and viscoelastic dampers so that a finite multidegree-of-freedom nonlinear system is obtained. stability of equilibrium equilibrium positions in the nonlinear system is then analyzed via a simplified two-degree-freedom model in an orbital reference frame. -plane motions of the tethered satellite system are studied numerically, taking the space environments into account. A large number of numerical simulations show that the tethered satellite system displays nonlinear dynamic characteristics, such as bifurcations, quasi-periodic oscillations, and chaotic motions.