A cutting-edge technology with the potential to enable crewed Mars missions and robotic exploration across the solar system was recently tested at NASA’s Jet Propulsion Laboratory in Southern California. On February 24, a team activated an electromagnetic thruster powered by lithium metal vapor, achieving power levels surpassing those of previous tests, completing its initial trial in a specialized JPL chamber. With continued development, these thrusters could play a crucial role in supporting human journeys to Mars.
The magnetoplasmadynamic (MPD) thruster project, under development for two and a half years, is led by JPL in partnership with Princeton University in New Jersey and NASA’s Glenn Research Center in Cleveland. Initiated in 2020 and funded by NASA’s Space Nuclear Propulsion project, the aim is to create a megawatt-class nuclear-electric propulsion system for human missions to Mars by targeting five key technology areas, including the electric propulsion subsystem.
This prototype surpassed the power levels of all current electric thrusters used by NASA spacecraft. Data gathered from this first firing will guide future test campaigns. Over the course of five ignition tests, the thruster’s tungsten electrode glowed brilliant white, reaching temperatures above 5,000 degrees Fahrenheit. The experiments took place at JPL’s Electric Propulsion Lab, which houses the nation’s only dedicated facility for safely testing electric thrusters that use metal-vapor propellants at megawatt-class power levels.
“At NASA, we work on many things at once, and we haven’t lost sight of Mars. The successful performance of our thruster in this test demonstrates real progress toward sending an American astronaut to set foot on the Red Planet,” said Jared Isaacman, a NASA Administrator. “This marks the first time in the United States that an electric propulsion system has operated at power levels this high, reaching up to 120 kilowatts. We will continue to make strategic investments that will propel that next giant leap.”
Electric propulsion systems consume up to ninety percent less propellant than conventional high-thrust chemical rockets. Modern electric thrusters, such as those on NASA’s Psyche mission, rely on solar energy to accelerate their propellant, producing a gentle yet continuous thrust that gradually builds to high velocity speeds of 124,000 mph. In recent tests, the team achieved power outputs of 120 kilowatts—more than 25 times the Psyche mission’s thrusters.
The team aims to reach 500 kilowatts to 1 megawatt per thruster, but a major challenge is ensuring the components can withstand high temperatures during extended operation. Crewed Mars missions may require 2 to 4 megawatts of power, meaning multiple MPD thrusters must operate reliably for over 23,000 hours. Once fully developed and paired with a nuclear power source, lithium-fed MPD thrusters could deliver the high thrust and efficiency needed for these missions, reducing launch mass and supporting heavy payloads.
