Metal Plasma Thruster for Small Satellites

This paper describes a metal plasma thruster (MPT) that is suited to nano- and microsatellites. The MPT uses solid metal propellant (hence requires no liquids, gases, flow valves, or flow controls), has no moving parts, generates approximately , and may be packaged into , 1-U, and multiple-U increments. A vacuum arc generates a metal plasma plume that accelerates into space at (platinum, Pt) to (magnesium, Mg) to generate thrust . The range of specific impulse is from 693 s (Pt) up to 3119 s (Mg). Spacecraft interface is simple: the autonomous MPT requires only a DC input (7–28 V) and a start/stop control pulse from the satellite. The MPT is simpler and more rugged than ion engines and Hall thrusters, which are not easily scaled down in mass and power for satellites, and provides superior total impulse per kilogram. The MPT is easier to operate than equivalent-sized alternatives: field emission electric propulsion thruster, xenon gas radiofrequency thruster, and pulsed plasma thruster.