Gridded ion thruster

The gridded ion thruster is a common design for ion thrusters, a highly efficient low-thrust spacecraft propulsion method that runs on electrical power and uses high-voltage grid electrodes to accelerate ions with electrostatic forces. Propellant atoms are injected into a discharge chamber and ionised into a plasma, by electron bombardment in the Kaufman type, by radio frequency oscillation or by microwave heating. The ion engine was first demonstrated by the German-born NASA scientist Ernst Stuhlinger and developed in practical form by Harold R. Kaufman at the NASA Lewis Research Center from 1957 to the early 1960s. It was first flown in space on the SERT-1 test in 1964, and later powered the Deep Space 1 probe and the Dawn asteroid mission.