Moon & Mars Orbiting Spinning Tether Transport - Tethers Unlimited

Tethers Unlimited, Inc.Appendix K: Facility Reboost StudyResultsFigure 2 shows the orbit semimajor axis and eccentricity during the three days of boosting. It alsoshows the thrust efficiency calculated during periods of thrusting. Figure 3 shows the altitudes of theorbit perigee and apogee, as well as the perigee velocity.Orbit Boost Rates:The semimajor axis increases at 42.9 km/day. Note that if the electrodynamic boost system adds energyto the orbit at a constant rate, the rate of semimajor axis increase will accelerate due to the inverse relationbetween orbital energy and semimajor axis.The eccentricity increases at 0.0026/day. Note that the eccentricity change rate will also vary duringSemimajor Axis (km)9550950094500 0.5 1 1.5 2 2.5 3Time (days)0.295Eccentricity0.290.285Thrust Efficiency (µN/W)0 0.5 1 1.5 2 2.5 3Time (days)60402000 0.5 1 1.5 2 2.5 3Time (days)Figure 2. Semimajor axis, eccentricity, and thrust efficiency during the first three days of thereboost operation.K-4