Assessment of Rocketborne and Airborne Infrared Data

Past DNA/AFGL aircraft data on 2.8 micron-band emission from the auroral particle-irradiated atmosphere were systematically evaluated, and a detailed plan was formulated for measuring its spatial-temporal variations with a radiometer of much higher angular and intensity resolution and for interpreting this structure in terms of aeronomy code models. Data from HAES-program sounding rocket A18.219-1 are presented that show a large, unexpected enhancement of the near-limb 4.2-4.3 micron radiance 90 km altitude closely associated in time and space with energy input from incoming charged particles. In addition energy deposition within the field of the interferometric spectrometer HIRIS II was calculated from optical (and incoherent-scatter radar) data taken at ground stations; SWIR radiometry results from another rocket probe were found to be consistent with results from other HAES investigations; and infrared/optical measurements of concentrations of minor species important in atmospheric deionization are suggested (in three Appendixes). Most, but not all, of the enhancements in radiation from the zenith atmosphere near 2.8 micron measured by the aircraft's wide-field radiometer show no statistically-significant difference from one another. Interpreted as nitric oxide overtone emission, the energy yield of the complete vibrational-cascade sequence derived from this subset is 0.4 (sub 5)%.