By Research Support Instruments (RSI)
The NRL Special Sensor Ultraviolet Limb Imager (SSULI) optical instrument is a spectrograph with the objective to measure extreme and far ultraviolet radiation (vertical profiles) from the Earth's limb. The primary observations, ranging from 80 - 170 nm (FUV/EUV), with 1.5 nm resolution, are of radiation from atomic oxygen and nitrogen, and molecular nitrogen, resulting in direct measurements of the electron density vertical profile as well as ion and neutral densities. The vertical profiles in the upper atmosphere and ionosphere are obtained by viewing the Earth's limb at a tangent altitude of approximately 50 km to 750 km. Data products from the SSULI were officially transitioned for use in operational systems at the Air Force Weather Agency (AFWA) on June 9, 2011. RSI designed and built the SSULI UV limb imaging spectrometer under contract to NRL. Additional RSI SSULI work was in the areas of systems science, radiation analysis and testing, contamination analysis, and providing liaison between the program scientists and the design and fabrication efforts. RSI was also responsible for the SSULI pre-flight SIC mirror lifetime testing.
