Autonomous Field Emission Cathodes for Electrically Propelled Nanosats

The objective for this Phase I program is to lay the foundation for the development of an autonomous electron source for use with electrically propelled nanosats. Electric propulsion offers high specific impulse, and in the case of electrodynamic tethers, "propellant-less" operation. The electron source will be based upon field emission from C-nanotubes. It will function as a "drop-in" component with simplified interface to nanosat power supply and controls. The project will develop a low-cost fabrication technique for field emitter arrays and integrate the array in a small package that combines power and control electronics. Cost will be as important a benchmark as performance. Current capabilities are expected to range up to 1 mA and operating voltages should be < 100 volts, depending on the electrical current requirements. For nanosat applications, where currents in the microamp range will be needed, operating voltages < 50 volts should be obtained. The unit will be capable of operating from a low voltage spacecraft power supply.