Preliminary Analysis on the Quick Disposal of Used H-II Upper Stage by Electrodynamic Tether

Abstract

This study proposes an application of the electrodynamic tether to deorbit a spent H-II upper stage to reduce space debris. In such an application, the induced current flows through the tether wire by the tether motion that intersects the geomagnetic field, and the Lorentz force is induced in the opposite direction of tether motion, namely, the direction of the decelerating system, by the interaction between this induced current and the geomagnetic field. The concept is basically the same as that of a ProSEDS space experiment, which is proposed by NASA’s Marshall Space Flight Center. But the main difference is its orbit. The orbit of spent H-II upper stage is ellipse, although the orbit of ProSEDS is circular. So the operation and dynamics are different compared with those of ProSEDS. In this study, the performance of an H-II upper stage deorbit system by electrodynamic tether is analyzed by the mission analysis model, and the presumable dynamics of this system is also shown. The results show that this system can deorbit an H-II upper stage in a few months, but there is a possibility that the performance of deorbit will degrade if a rotation of the tether system is occurred.