Small Satellite Constellations for Measurements of the Near-Earth Space Environment

A constellation of small satellites is well suited to making measurements of the near-Earth space environment given the spatial and temporal variability that preclude solely independent, localized measurements. In this chapter we discuss some of the factors that must be considered when designing a system for space weather monitoring and the scientific investigation of the near-Earth environment. Some important parameters include: (1) the number flux and energy of energetic particles in the auroral region and/or the radiation belts, (2) the number density temperature and composition of neutrals and ions in the upper atmosphere, (3) the wind speed in the upper atmosphere, (4) the ion drift velocity and/or DC component of the electric field, and (5) small scale fluctuations in the ionosphere that lead to radio scintillation. An integrated solution will be addressed that spans the range of potential science objectives, enabling sensor technologies, triple-cubesats (<5 kg) and nanosatellite (<50 kg) system design, secondary launch options, and the associated data processing and distribution plan. In addition, details related to a JHU/APL effort with a planned 2010 mission schedule to serve the requirements of user communities for near-Earth space environment and space weather data will also he discussed.