Moon & Mars Orbiting Spinning Tether Transport - Tethers Unlimited

Tethers Unlimited, Inc.MMOSTT Final ReportVI.CONCLUSIONSThe Phase I and II NIAC-funded efforts evaluated the feasibility of using rotating spacetethers to serve as the backbone of a reusable in-space transportation infrastructure. We beganby developing concept designs for tether systems for LEO-to-GTO, LEO Lunar, andEarthMars transport, and used numerical and analytical tools to demonstrate that thesesystems can be designed to account for the complex orbital dynamics in the Earth-Moon system.We then developed a realistic system-level design of a tether boost facility, based upon presentdayand near-term technologies, and evaluated the components and technologies required forthis system in terms of technology readiness. The two most important key technology needsidentified by this study were the rendezvous and capture to enable a tether to reliably pick up apayload, and the high-power electrodynamic tether propulsion systems needed to providepropellantless reboost of the tether facility in between payload transport operations. Weinvestigated these two technology needs further, developing concept designs for methods tomake these challenges solvable, and demonstrated their feasibility using detailed numericalsimulations. To continue developing the technologies needed for Momentum-Exchange/Electrodynamic-Reboost tether systems in an affordable manner, we developed aconcept design for a small initial tether boost demonstration experiment that could fly as asecondary payload on a GEO satellite launch, and could boost a microsatellite to a lunartransfer. This experiment will serve as the first step in an incremental technology developmentplan, in which an Earth-Moon-Mars tether transportation system could be deployed in stages,and each stage could perform useful transportation missions to generate revenue to fund thedevelopment and deployment of the rest of the system.19