Nanosat Technology And Managed Risk; An Update Of The CYGNSS Microsatellite Constellation Mission Development

Existing and forecasted budget constraints continue to drive innovative solutions for space-based mission applications. NASA’s Earth science mission, the Cyclone Global Navigation Satellite System (CYGNSS) was selected as part of NASA's Earth Venture program with a total mission cost cap (excluding launch vehicle) of $103M. Performing valuable science at low cost is only possible given technology innovation and a development risk posture higher than typically accepted for NASA missions. CYGNSS is being designed to address present tropical cyclone intensity forecasting deficiencies. These deficiencies are thought to be the root cause for essentially no improvement in the accuracy of the storm’s intensity prediction (Classification and Category levels) since 1990 while tropical storm track forecasts have improved in accuracy by ~50%. The mission will combine the all-weather performance of GNSS bi-static ocean surface scatterometry with the sampling properties of a satellite constellation to provide science measurements never before available to the tropical cyclone operational and research communities. The mission cost cap dictates that the CYGNSS flight segment of 8 Observatories, each carrying a 4-channel GPSbased scatterometer, all be launched on a single launch vehicle. The mission will demonstrate how recent developments in nanoand micro-satellite technology integration, including recent developments in star trackers and reaction wheels, when combined with a managed risk approach, can be applied as cost effective solutions to fill capability voids of large-scale observatories. CYGNSS will also demonstrate low cost science mission operations, how to safely deploy a constellation from a single launch vehicle without collision, and a low-cost method for constellation configuration management. The CYGNSS SmallSat 2014 paper will provide an update of the mission system development status, an overview of how a synergistic approach between flight and ground segments enables a cost effective science mission solution, and a description of our approach to constellation configuration control.