The retarding ion mass spectrometer (RIMS) instrument on Dynamics Explorer 1 has carried out high-altitude measurements of the polar wind. During an outbound pass through the outer plasmasphere and plasma trough at 0900 LT the RIMS instrument measured the detailed characteristics of the thermal and suprathermal ions. Three distinct populations were observed: (1) thermal ions (H+ and He+) with densities ranging from >500 ions/cm3 to 30 km/s and > 15 km/s with an H+/He+ flux ratio of 3 to 10. Best-fitting techniques for the H+ and He+ streaming distributions indicate a supersonic flow, although the data cannot be interpreted unambiguously. These comprehensive measurements of thermal and suprathermal plasma characteristics are interpreted in terms of plasmasphere refilling processes.