Auroral ionospheric E region parameters obtained from satellite-based far-ultraviolet and ground-based ionosonde observations—effects of proton precipitation

At the nadir, there are ∼57.5 pixels per averaging area for GUVI and ∼28.5 for SSUSI. Only 0.030 counts per R per averaging area for GUVI, F16 SSUSI, and F18 SSUSI, respectively.