SHUTTLE CHARGING BY TETHER CONTROLLED ELECTRON-BEAM

During the reflight of the tethered satellite system, the electron gen erator assembly (EGA) emitted steady electron beams six times with the satellite deployed between 6.2 and 16.1 km. Maximum beam energies and currents were 1.65 keV and 0.4 A, respectively. Data presented here s how that: (1) emissions create local electron clouds that can charge t he shuttle, (2) ionization of thruster gas by beam electrons in the sh eath did not reduce the shuttle potential, (3) the EGA utilizes more t han half the induced potential, and (4) ionospheric density gradients and magnetic field orientations affect the circuit's potential distrib ution.