Abstract

High altitude measurements of spectrally-resolved atmospheric infrared fluorescence provide the necessary input for upper atmospheric model verification and refinement. Perhaps the most definitive survey of infrared radiance in the quiescent upper atmosphere was completed in the SPIRE measurement program conducted by the Air Force Geophysics Laboratory. In this mission a rocketborne instrumentation package was launched into the dawn terminator over Poker Flats, Alaska, in September of 1977. The goal of the program was to measure the atmospheric limb infrared radiance for tangent heights between hard earth and 250 km under both sunlit and dark conditions. To achieve this, the payload was sequentially scanned through the earth limb and was oriented at different angles relative to the sun. In this manner regions with a variety of illumination times were observed. One of the diagnostics employed on this flight was a liquid-helium-cooled circular variable filter (CVF) spectrometer capable of monitoring long-wavelength infrared emission in the 8.7 - 16.5 μm region with a spectral resolution of approximately 2% of the wavelength.

© 1983 Optical Society of America