During the TSS-1R flight, conditions occurred under which very intense currents flowed through the tether wire system. The effect of these currents during the active phases of operation was clearly seen by the TEMAG sensor assembly located on the short, fixed satellite boom. Magnetic signatures appeared on the field components parallel to the boom and to the spin axis with a strong peak when the boom points closer to the ram direction. While a toroidal current flowing on the ram side of the plasma sheath may explain the main features seen by the TEMAG outboard sensor, further studies are needed for the physical interpretation of the complex electrodynamic interactions of the TSS-ionosphere system. ¿ 1998 American Geophysical Union