The Variable Specific Impulse Magnetoplasma Rocket (VASIMR®) engine is a new type of electric thruster with many unique advantages. In a VASIMR® engine, gas such as argon, xenon, or hydrogen is injected into a tube surrounded by a magnet and a series of two radio wave (RF) couplers The couplers turn cold gas into superheated plasma and the rocket’s magnetic nozzle converts the plasma thermal motion into a directed jet.