The results of the TSS-1R mission generated several scientific puzzles. First the current collection was much more efficient than predicted on the basis of theoretical models, and previous laboratory and rocket experiments. Second, a sharp transition in the interaction physics occurred at threshold potentials between 5--10 V. Third, a significant population of suprathermal electrons, heated ionospheric ions, and enhanced plasma waves were observed in the ram direction, following the transition. The letter contains a preliminary examination of the extent to which these phenomena are related to the interaction of the impinging ambient ram O+ ions with the sheath surrounding the TSS satellite. ¿ 1998 American Geophysical Union