Radar measurements in the cusp region, in close conjunction with the Freja satellite, show evidence of the ionospheric signature of the cusp. The intense low‐energy fluxes of ions and electrons associated with the cusp, and seen with the satellite, produce a distinct region of enhanced electron density and electron temperature in the ionospheric F‐region. The ionization due to the precipitating ions is rather weak, of the same order of magnitude, and maximizing at the same altitude, as the solar EUV ionization. That due to the electrons is much stronger, maximizes at higher altitude and is clearly identifiable in this case. This is partly because of the unusually high altitude of the cold, EUV and convection controlled F‐region, creating a distinct height difference as compared to the precipitation region, and partly because ion outflow prevents the cold daytime plasma from convecting into the precipitation region. A narrow region of high ion temperatures most likely indicating strong electric fields is seen within the precipitation region but is not coincident with the most intense precipitation. The equatorward boundary of the precipitation region is seen to move equatorward, while the convection of the plasma within the region is poleward.
