An euv spectrometer for monitoring the aurora

摘要

Aurora is a spectrometer optimized for measurements of the EUV flux of the aurora and the Earth plasmasphere in the emission lines of O~+, He and He~+. It is designed to be small and to operat from a microsatellite. It is basically an optical bench consisting of two grazing incidence spectrographs (channels). The first channel, EUV-1, operates in the wavelength band from 15 to 45 nm while the second channel, EUV-2, is sensitive from 55 to 85 nm. Aurora spectral resolution allows to obtain integrated fluxes of the aurora and/or airglow in the lines of He at 58.4 nm and of O~+ at 83.4 nm with the EUV-2 spectrometer. The EUV-1 channel provides integrated fluxes of the He~+ Lyman-#alpha# line at 30.4nm. The detector system, intensified CCD, and the instrument electronics are derived from our experience with UVSTAR. Aprototype of Aurora has flown attached to UVSTAR on the Discovery Shuttle flight no. STS-85.