Session
Technical Session IV: New Mission Concepts I
Abstract
The Student Nitric Oxide Explorer (SNOE) is a small scientific spacecraft designed for launch on a Pegasus™ XL launch vehicle for the USRA Student Explorer Demonstration Initiative. Its scientific goals are to measure nitric oxide density in the lower thermosphere and analyze the energy inputs to that region from the sun and magnetosphere that create it and cause its abundance to vary dramatically. These inputs are energetic solar photons in the EUV and X -ray spectral regions, and energetic electrons that are accelerated into the polar regions, where they cause auroral disturbances and displays. Both of these phenomena are aspects of solar variability; thermospheric nitric oxide responds to that variability and in turn determines key temperature and compositional aspects of the thermosphere and ionosphere through its radiative and chemical properties. The SNOE ("snowy") spacecraft and its instrument complement is being designed, built, and operated entirely at the University of Colorado, Laboratory for Atmospheric and Space Physics (CU/LASP). The spacecraft is a compact hexagonal structure, 37" high and 39" across its widest dimension, weighing approximately 220 Ibs. It will be launched into a circular orbit, 550±50 km altitude, at 97.5° inclination for sun-synchronous precession at 10:30-22:30 solar time. It will spin at 5 rpm with the spin axis normal to the orbit plane. It carries three instruments: An ultraviolet spectrometer to measure nitric oxide altitude profiles, a two-channel ultraviolet photometer to measure auroral emissions beneath the spacecraft, and a five-channel solar soft X-ray photometer. The spacecraft structure is aluminum, with a center platform section for the instruments and primary components and truss work to hold the solar arrays. Power is regulated using switched arrays and a partial shunt. The attitude determination and control system uses a magnetometer, two torque rods, and two horizon crossing indicators to measure spin rate and orientation. Attitude control is implemented open-loop by ground commands. The command and data handling system is implemented using a single spacecraft microprocessor that handles all spacecraft and communications functions and instrument data. The communications system is NASA compatible for downlink using the Autonomous Ground Services station at Poker Flat; all mission operations, data processing, and analysis will be performed using a project operations control center (POCC) at the LASP Space Technology Research building.
The Student Nitric Oxide Explorer
The Student Nitric Oxide Explorer (SNOE) is a small scientific spacecraft designed for launch on a Pegasus™ XL launch vehicle for the USRA Student Explorer Demonstration Initiative. Its scientific goals are to measure nitric oxide density in the lower thermosphere and analyze the energy inputs to that region from the sun and magnetosphere that create it and cause its abundance to vary dramatically. These inputs are energetic solar photons in the EUV and X -ray spectral regions, and energetic electrons that are accelerated into the polar regions, where they cause auroral disturbances and displays. Both of these phenomena are aspects of solar variability; thermospheric nitric oxide responds to that variability and in turn determines key temperature and compositional aspects of the thermosphere and ionosphere through its radiative and chemical properties. The SNOE ("snowy") spacecraft and its instrument complement is being designed, built, and operated entirely at the University of Colorado, Laboratory for Atmospheric and Space Physics (CU/LASP). The spacecraft is a compact hexagonal structure, 37" high and 39" across its widest dimension, weighing approximately 220 Ibs. It will be launched into a circular orbit, 550±50 km altitude, at 97.5° inclination for sun-synchronous precession at 10:30-22:30 solar time. It will spin at 5 rpm with the spin axis normal to the orbit plane. It carries three instruments: An ultraviolet spectrometer to measure nitric oxide altitude profiles, a two-channel ultraviolet photometer to measure auroral emissions beneath the spacecraft, and a five-channel solar soft X-ray photometer. The spacecraft structure is aluminum, with a center platform section for the instruments and primary components and truss work to hold the solar arrays. Power is regulated using switched arrays and a partial shunt. The attitude determination and control system uses a magnetometer, two torque rods, and two horizon crossing indicators to measure spin rate and orientation. Attitude control is implemented open-loop by ground commands. The command and data handling system is implemented using a single spacecraft microprocessor that handles all spacecraft and communications functions and instrument data. The communications system is NASA compatible for downlink using the Autonomous Ground Services station at Poker Flat; all mission operations, data processing, and analysis will be performed using a project operations control center (POCC) at the LASP Space Technology Research building.
