The eerie blue exhaust trail of an ion thruster during a test firing. A quartet of these highly efficient T6 thrusters is being installed on ESA’s BepiColombo spacecraft to Mercury at ESA’s ESTEC Test Centre in Noordwijk, the Netherlands.
NASA Evolutionary Xenon Thruster (NEXT) in operation. NASA's new solar-electric propulsion thruster uses xenon ions for propulsion. The thruster can provide higher spacecraft top speeds than any other rocket currently available.
ion thruster - a form of electric propulsion used for spacecraft propulsion that creates thrust by accelerating ions. The term is strictly used to refer to gridded ion thrusters, but may often more loosely be applied to all electric propulsion systems that accelerate plasma, since plasma consists of ions. Ion thrusters are categorized by how they accelerate the ions, using either electrostatic or electromagnetic force.