Direct current arc plasma thrusters for space applications: basic physics, design and perspectives

Renewed interest in space exploration and aspirations for colonization of Mars, Moon and possibly other extra-terrestrial bodies puts pressure on the present-day space technology to become more efficient. Space engines, or thrusters, are the key element of any spacecraft and thus, continuous improvement in thruster design and performance is needed to realize the mankind’s goal of becoming a truly space faring civilization. Space micropropulsion systems that utilize plasma and electric fields to accelerate and expel mass to produce reactive thrust are advanced propulsion systems that can deliver very high specific impulse. In this review, we outline basic physical principles and design approaches for future direct-arc plasma propulsion systems. We then examine major obstacles and prospects for application of direct-arc plasmas in this type of space thrusters.