AeroAstro proposes decomposing nitrous oxide (N2O) as an alternative propellant to existing spacecraft propellants. Decomposing N2O can be used as either a high Isp, hot-gas monopropellant or as a low Isp, cold gas for ACS thrusters. AeroAstro further proposes to use an innovative technique to achieve N2O decomposition: gasdynamic resonance. Gasdynamic resonance will elevate the N2O to the activation temperatures required for exothermic decomposition, allowing monopropellant operation without the difficulties of a catalyst. One of the challenges of long-duration space exploration systems is finding a propellant for microspacecraft that is safe, reliable, robust, and performs better than current propulsion systems. N2O can replace both hot-gas propellants such as hydrazine and cold-gas ACS systems such as nitrogen or isobutane. N2O is non-toxic, has a low freezing point (-91o
C), and stores as a liquid. N2O is also a byproduct of the catalysis of ammonia, a main effluent of waste-water recycling systems for long-duration manned space missions. The anticipated results of this effort are data demonstrating the operating parameters of resonating N2O, and a dual-mode thruster design capable of both hot-gas and cold-gas operation. Phase II activity will evolve the design of the dual-mode thruster and demonstrate operation over a range of conditions.