For five separate ignitions on 24 February 2026, a tungsten electrode inside a vacuum chamber at NASA’s Jet Propulsion Laboratory glowed white, with temperatures climbing above 5,000 degrees Fahrenheit. A red plume streamed from the nozzle. The prototype was drawing up to 120 kilowatts.
That is the headline figure. The claim is a strong one: NASA says it is the first time an electric propulsion system in the United States has run at such power. The catch is in the comparison. JPL puts the test at more than 25 times the power of the thrusters now flying on the Psyche mission, which are the strongest electric engines on any NASA spacecraft today.
How the engine works
The machine is a lithium-fed magnetoplasmadynamic thruster, or MPD. It turns lithium metal into vapor and then uses electric currents and magnetic fields to fling the plasma out at high speed. Scientists have studied the idea since the 1960s. It has never flown operationally.
The appeal is efficiency. Electric propulsion uses up to 90% less propellant than chemical rockets, though it delivers a gentle, continuous push instead of a sharp kick. A higher-power engine promises more of that push without giving up the fuel savings.
“It’s a huge moment for us because we not only showed the thruster works, but we also hit the power levels we were targeting,” said James Polk, a senior research scientist at JPL.
What the test did not show
On closer reading, this is a first step. The SpaceDaily analysis notes that JPL’s April announcement described an initial laboratory test, not an endurance run or a flight qualification. The lab has not published measured thrust, efficiency or specific impulse at 120 kilowatts, and those numbers decide whether the power level turns into a usable spacecraft engine.
The gap to a real mission is wide. Researchers want to push each thruster to between 500 kilowatts and 1 megawatt. A crewed trip to Mars could need 2 to 4 megawatts in total, which means several MPD thrusters running for more than 23,000 hours, about 2.6 years of continuous operation by SpaceDaily’s arithmetic. Five ignitions are not that. Keeping the hardware alive at extreme temperatures is, in JPL’s own account, one of the biggest technical hurdles.
Who is paying
The project has been under development for 2½ years, a collaboration between JPL, Princeton University and NASA’s Glenn Research Center in Cleveland. The money comes from NASA’s Space Nuclear Propulsion project, which began in 2020 to support megawatt-class nuclear electric propulsion for Mars.
NASA Administrator Jared Isaacman framed it as a sign that the agency has not dropped Mars. “We will continue to make strategic investments that will propel that next giant leap,” he said.
Sources
- NASA Fires Up Record-Breaking Plasma Thruster for Future Mars Missions (JPL release, via SciTechDaily)
- Mission Notes: lithium MPD thruster test analysis (SpaceDaily)
