NASA's 2015 technology roadmap recognizes the importance of electrospray propulsion to primary propulsion, formation flight and attitude control of small (3U-6U) spacecraft. Specific applications include asteroid scouting missions along with lunar and interplanetary missions. Additionally, the proposed electrospray system is ideal for drag-compensation applications for long term earth observation (EO) missions at altitudes as low as 200km. Furthermore, the technology continues to have numerous applications to scientific spacecraft of all sizes where high precision, low thrust systems permit extremely accurate attitude and station keeping. The latter functionality has been recently demonstrated in-space by Busek's colloid thrusters on the NASA ST7/ESA LISA Pathfinder mission. The highly scalable nature of the technology, both in terms of thrust and deltaV, without loss of performance is a critical feature permitting applicability to this wide spectrum of functions. However, lifetime limitations and scalability to sufficient thrusts are recognized as present gates to reliable realization of CubeSat scale high deltaV systems.Busek has proven both the functional feasibility and lifetime potential of colloidal/electrospray propulsion through the ST7/LISA spacecraft program. Through integrating that heritage and addressing the life-limiting issues of passively fed electrospray thrusters, Busek aims to bring the full potential of electrospray propulsion to 3U/6U spacecraft platforms Compact propulsion systems that are scalable in both thrust and deltaV without loss of performance are an enabling technology for CubeSat missions and therefore have numerous commercial applications. The market size for the proposed system is accordingly very large. Potential non-NASA customers include commercial asteroid prospecting, DoD and commercial EO missions. Numerous LEO CubeSat mission durations could be extended through the drag-compensation capabilities of the proposed system. De-orbiting applications are particularly relevant to new LEO telecommunication and EO initiatives. International consensus is forming around the need for orbital debris management, which poses risks to functioning space assets. It is likely that in the near future, international agreements will require provisions in spacecraft design to reposition satellites to disposal orbits, or to completely deorbit them. Safe/unpressurized long-term propellant management and minimal mechanical/moving parts, issues addressed in this project, will be critical to de-orbit applications.
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