SPT-140 is a solar-powered Hall-effect ion thruster, part of the SPT-family of thrusters. SPT stands for Stationary Plasma Thruster. Like other members of the SPT series, it creates a stream of electrically charged xenon ions accelerated by an electric field and confined by a magnetic field.
The thruster is manufactured by the Russian OKB Fakel, who collaborated during development with NASA's Glenn Research Center, Space Systems Loral, and Pratt & Whitney beginning in the late 1980s. It was first tested at the Plasmadynamics and Electric Propulsion Laboratory in 1997. In 2002, it was tested as a 3.5 kW unit by the United States Air Force as part of its Integrated High Payoff Rocket Propulsion Technology program. In 2023, the thruster was launched aboard NASA's Psyche spacecraft.
