Determination of the jump in electrostatic potential at the earth's bow shock front by selective measurements of the ion components in the solar wind

We have examined the jumps in velocity and temperature of the proton and alpha-particle components in the solar wind when the wind intersects the Earth's bow shock. The jumps were measured by means of selective detectors of the SKS energy spectrometer on the satellites Prognoz 7 and 8. On the basis of energy balance, we determine the jump in the electrostatic potential at the shock front: on the average, it amounts to about 300 V