Stratospheric satellites for Earth science applications

We present a concept for global and regional constellations of low cost stratospheric satellites based on ultra long duration balloon (ULDB) and StratoSail/spl reg/ Trajectory Control System (TCS) technologies. Stratospheric Satellites (StratoSat/spl trade/ platforms) will be moved around the globe by stratospheric winds (at the height of 35 km - above 99% of the Earth's atmosphere, virtually "at the edge of space"), have some maneuvering capabilities, and have a multitude of Earth Science applications, such as measuring profiles of concentrations of ozone and trace constituents, monitoring Earth magnetic field and radiative fluxes, tracking hurricanes, and monitoring global weather and climate. Networks of StratoSat/spl trade/ platforms can be configured to provide independent observations and to validate observations of other sensors within the SensorWeb paradigm of the NASA Earth Science Vision. The StratoSat/spl trade/ platforms utilize a small amount of trajectory control to meet observation objectives. This capability allows for rapid adaptation of network configuration to observational needs. The network can be configured to provide observations with a desired frequency over specific target areas, such as the tropics or polar regions. We describe the design of StratoSat/spl trade/ platforms, potential mission scenarios and payloads, and potential network configurations.