Ultraviolet remote sensing of the aurora and ionosphere for C3I system use

The capabilities of the auroral ionospheric mapper (AIM) on board the HILAT satellite are described and observational data are discussed. AIM features a spectrometer which is sensitive to 1100-1900 A emissions with 30 A resolution. The instrument was built to function in either imaging or spectrometer modes. Early results have demonstrated that the auroral arcs can be discriminated above daytime emission levels. A capacitor failure after the acquisition of 50 images has reduced the AIM functions to a photodetector mode only, with no imaging. Sample auroral images of the arcs reveal incoming 1-10 kV electrons and protons which collide with atmospheric gases and cause ionization, excitation and emissions at UV wavelengths. The data have encouraged plans for the manufacture and launch of a new instrument with enhanced capabilities. 12 references