Moon & Mars Orbiting Spinning Tether Transport - Tethers Unlimited

1 ScopeThe MMOSTT system is an in-space transportation system that incorporates an Earth-orbiting facility witha spinning tether as a primary element. This document describes the top-level system requirements for atether boost facility in low Earth orbit. The requirements defined here are for the objective system, that is,for a facility that is part of an operational full-scale transportation system that boosts payloads from lowEarth orbit to higher orbits or Earth escape. Requirements for sub-scale or demonstration systems may bedescribed at a future date in other documents. Requirements for tether facilities in higher Earth orbits or inorbits about other planetary bodies may be described at a future date in other documents.The tether facility consists of the tether, a control station, and a grapple assembly. The control stationcontrols the tether and tether dynamics. The grapple assembly captures and releases payloads.A payload is any object that will be accelerated or decelerated toward a destination in space. Thetransportation system includes a payload accommodation assembly to provide the interface between thepayload and the grapple assembly on the tether facility.This document describes requirements including a nominal payload mass and a nominal release orbit. It isenvisioned that the tether facility will be able to grapple payloads with greater or lesser mass than nominaland release them after imparting less or more delta-v, respectively, than nominal. However, norequirements are imposed on the delta-v that must be imparted to non-nominal payloads, except that thesystem can deliver a smaller payload to the same release orbit as a nominal payload. The tether facility isenvisioned to accommodate modular assembly and growth, so its capacity may be expanded to handlelarger payloads if a need arises.