We present rest frame ion distributions computed from three-dimensional observations of upstream superthermal ions gained by the Universtiy of Iowa Quadrispherical Lepedea on ISEE-1. The observations are for a single inbound, midmorning pass starting upstream from the ion foreshock and continuing across the quasiparallel bow shock into the magnetosheath. The crossing of the ion foreshock boundary is marked by a several minute burst of ions of temperature 100--200 eV moving along the IMF away from the bow shock at 500 km/s relative to the solar wind. The observation of these 'reflected' ions is followed by an extended interval of 'diffuse' ions of temperatures 2--3 keV flowing at ~250 km/s relative to the solar wind and persisting until the bow shock is crossed. The diffuse ion &bgr; has a value of approximately 6 in the region of the superthermal ions, exceeding the normal thermal &bgr; of the solar wind by roughly an order of magnitude. Both types of superthermal ions constitute roughly 2% of the total ion density and carry a parallel heat flux of ~2¿10-2 ergs cm-2 s-2. When integrated over an assumed 10¿10 RE bow shock emission area, this implies an upstream dissipation that may approach 1017 to 1018 ergs/s, comparable to a modest substorm. |