How do ion thrusters work ?
These rocket engines use arrays of solar panels to power electrode grids. The large electrostatic fields created by the grids accelerate xenon ions to very high exhaust velocities. A characteristic of these engines is high specific impulse (and hence high exhaust velocity) and low propellant mass flow rate. For example, the NASA Solar Electric Propulsion Technology Applications Readiness (NSTAR) thruster has a specific impulse of 1700 – 3300 seconds (an exhaust velocity in the order of 30 KILOMETERS per second) compared to a chemical rocket which has a specific impulse of around 300 seconds (an exhaust velocity in the order of 3 kilometers per second). The NSTAR thruster has a propellant mass flow rate of a few milligrams per second compared to a chemical rocket’s mass flow rate of a few kilograms per second. Thus the ion thruster can be employed for maneuvers over extended periods of time while still using a low amount of propellant. The cost savings due to the reduced weight of these
