Description: To address the NASA need for high-thrust electric propulsion technologies that enable/enhance mission capabilities such as attitude control and dual manifest launch opportunities, Physical Optics Corporation (POC) proposes to develop a new Balanced Electric Spacecraft Thruster (BEST) system, which is based on a novel thruster design and a new system integration. Specifically, the innovation in the propellant accelerator and a design with no charge neutralization will enable the device to fully use the potential of any ionic liquid monopropellant, including the advanced energetic monopropellant AF-M315E, the "green propellant." As a result, this technology offers balanced and throttled high thrust and variable impulse per unit of volume, which allows for the control of attitude and high efficiency, which directly address NASA's Small Spacecraft Technology Program. In Phase I, POC will demonstrate the feasibility of the BEST approach by the combination of proof-of-concept analysis and experiments with the BEST conceptual prototype to reach TRL-3. In Phase II, POC will design and build a BEST prototype, measure its performance and plume characteristics, demonstrate and deliver it to NASA to achieve TRL-6 at the end of Phase II activities.

Benefits: The proposed concept is further improvement of a colloidal thruster by a novel approach to particle acceleration. As a result, high exit velocity of charged particles and wide range throttling are achievable at a reduced magnitude of applied voltage and full use of the mass of propellant. As an example of electrical propulsion, the proposed thruster utilizes renewable solar energy, thus significantly reducing the launch mass of a spacecraft or satellite. Thus, NASA's related applications include all missions requiring high thrust per unit of consumed power, especially ones where power is limited, and missions requiring attitude control, provided here by the ability to vary specific impulse and thrust. Examples of related NASA missions include the Nodes technology demonstration mission, the CubeSat Proximity Operations Demonstration mission, the Pathfinder Technology Demonstrator mission, and other NASA's missions in science, exploration, space operations, and aeronautics, including those with crosscutting applications for NASA and other users. The proposed thruster concept is directly related to the Small Spacecraft Technology Program's current focus areas such as a propulsion, pointing, and autonomous operations.

While small spacecraft, including military surveillance and GPS satellites, are currently delivered to space by traditional, chemical propulsion thrusters, electrical propulsion is the growing trend in orbit correction and maneuver. It enables dedicated ride-sharing, where an integrator books a complete launch mission and sells the available capacity to multiple spacecraft operators without the need for a primary customer. Solar electrical propulsion resolved the issue with electric power, but the use of separate propellant (from chemical thrusters) limits the lifetime of electrical thrusters. The implementation of multimode propulsion, i.e., sharing propellant with chemical propulsion drives, significantly extends the lifetime of electrical thrusters. Another attractive field for low-thrust electrical propulsion is the market in nanosatellites and microsatellites. These miniaturized, low-cost satellites are designed for commercial, communication, and space research purposes. Continual reduction in the cost of nanosatellites and microsatellites, increasing demand across verticals, and increases in the number of application areas, are expected to remain the major drivers behind increased traction in the nanosatellite and microsatellite market. Therefore, the compact, high thrust, impulse density thruster will benefit NASA's Small Spacecraft Technology Program as well the military space programs.