Studies of a direct-current microdischarge based miniaturized plasma thruster

Presented are the results of preliminary investigations of a direct-current microdischarge based miniaturized plasma thruster called a Microdis-charge Plasma Thruster (MPT). The MPT has a triode con¦guration consisting of electrodes made of molybdenum separated by mica dielec-tric with argon propellant. Several variations of the triode were studied in order to determine a con¦guration that provided a relatively stable con¦guration. The thruster can produce an intense plume with a bluish outline. Currentvoltage characteristics of the thruster are reported. Preliminary spectral measurements reveal that the plume emission arises from excited ground states of argon, with no emission from argon ions detected.