The APPJ has the advantage that the plasma is ejected from a device (up to several centimeters) and travels to the surface to be sterilized. Eagle Harbor Technologies (EHT), Inc. is proposing to develop a large-area APPJ for spacecraft surface sterilization. EHT will leverage the previously developed EHT nanosecond pulser, which provides unprecedented control of output voltage, pulse width, and pulse repetition frequency. This capability will allow EHT researchers to develop and optimize an APPJ for surface sterilization.