Space-Clock Elevator: Multi-Stage Orbital Transport via Rotating Tethers and Elliptical Nodes

Abstract

Rotating space tethers have long been proposed as momentum-exchange devices capable of transporting payloads between orbital regimes without continuous propellant expenditure, offering a potential alternative to conventional propulsion for transfers from low Earth orbit to higher orbits. In this work, we numerically investigate a system of multiple rotating tethers distributed across different orbital radii and coupled through intermediate transfer platforms (elliptical nodes) moving along Keplerian trajectories. We identify families of dynamically consistent configurations in which neighboring tethers achieve near-phase synchronization, enabling coordinated payload exchange without impulsive maneuvers. Based on these results, we introduce the concept of a Space-Clock Elevator: a modular orbital transport architecture in which payloads are transferred sequentially between synchronized rotating tethers via intermediate elliptical nodes. Numerical experiments demonstrate that such synchronized tether networks can support outward payload transport while maintaining bounded tether tension and dynamically stable orbital motion.