Moon & Mars Orbiting Spinning Tether Transport - Tethers Unlimited

trajectories in which, if the payload is not captured, it is lost in space. Also, in the early operationsbefore extensive ballast mass is accumulated, care must be taken that the tether itself is notaccelerated to hyperbolic velocities as a result of the momentum exchange.Tethers orbiting planets with magnetic fields can also have a small conductive portion of thetether that would use electrodynamic tether propulsion[9,13], where electrical current pumpedthrough the tether pushes against the magnetic field to add or subtract both energy and angularmomentum, thus ultimately controlling the total energy and angular momentum of the orbitingtether system. This can be used to make up energy losses in a MERITT-type system, or performorbital maneuvers about Jupiter.Periapsis ofAerobrakingExit OrbitTether Orbit Outbound StateHigh Energy, PeriapsisRotated Counter-clockwiseAerobrakingPrimaryLinesSecondaryLines(initially unstressed)0.2 to10's ofmetersFirst Levelof SecondaryLinesRedistributesLoad toAdjacentNodesSeveredPrimaryLineEffects ofDamageLocalizedSecondLevelof SecondaryLinesRedistributesLoadBack toUndamagedPortion ofPrimary LinePlanetOrbitPeriapsis ofInboundHyperbolaTether OrbitInbound StateLow Energy0.1- 1 metera. b.c.PayloadInboundTrajectoryPayloadOutboundTrajectoryFigure 5. Hoytether damage resistanceFigure 6. Tether concept for inbound andoutbound payloads at Earth or MarsMarsWhip tether energy management can be aided by including a solar arrays to power a tetherwinch to periodically change the tether length at the proper point in the MarsWhip ellipticaltrajectory [17,18], making the orbit more or less elliptical for the same angular momentum. Thispower could also run an fuel-efficient electric propulsion systems using in-situ resources fromMars or its moons.We have not modeled long-term orbit perturbations of the planetwhip tethers, however, thechanges made to the tether orbits from frequent payload capture and release would dwarf anyperturbation effects, and minor adjustments in release angles and timing could be used to counteror enhance such effects as needed.The large number of free parameters in this system produce a "good news/bad news aspect toanalysis. The difficulty is that the problem is not self-defined and to make the model work, anumber of arbitrary choices must be made. The good news is that this means there is a fair amountof operational flexibility in the problem and various criteria can be favored and trades made.Fig. 6 shows how a single tether toss and catch system might work on either the Earth orMars end of the MERITT system.7