The scientists at Rosatom say they have developed a laboratory prototype of a plasma electric rocket engine based on a magnetic plasma accelerator, which exhibits improved thrust performance (at least 6 Newtons) and specific impulse (at least 100 kilometers per second).

The project is a part of a comprehensive program aimed at advancing nuclear science, engineering, and technology in Russia, which in 2025 emerged as a part of the new national initiative for technological leadership “New Nuclear and Energy Technologies”.

The average power of such an engine operating in a pulsed-periodic mode can reach 300 kilowatts. These engines enable spacecraft to accelerate in space to velocities that are beyond the capability of chemical engines and make fuel consumption more efficient by reducing the need for fuel by ten times, Rosatom said.

At present, a one-way travel to Mars onboard spacecraft with conventional engines can take almost a year, which poses a significant risk to astronauts considering cosmic radiation exposure. However, plasma engines could reduce the duration of flights to just 30 to 60 days, making possible return missions to Mars. The creation of a prototype is a crucial milestone of the project as it shows whether the engine is suitable for future nuclear tugs in space and whether it is possible to reduce the cost of their production.

—Alexey Voronov, First Deputy Director General for Science at Rosatom's Research Institute in Troitsk

As a comparison, SpaceX has stated that it aims for trips to Mars to take between 2 to 4 months one way (60 to 120 days). Current spacecraft using conventional chemical propulsion, such as NASA’s Perseverance rover, take about 7 months (210 days) to reach Mars, depending on planetary alignment and trajectory.

SpaceX intends to use advanced methane-oxygen Raptor engines in the Starship, orbital refueling, and optimized high-thrust trajectories to shorten the journey. Elon Musk has also suggested that with further refinements, the trip could eventually be as short as 1 month, though the 2-to-4-month range is the most consistently cited target for near-term missions.

A large-scale experimental facility is being constructed at Rosatom’s Troitsk site to test the plasma rocket engine prototype and other similar technologies. The diameter of the main equipment of the facility, the vacuum chamber, is 4 meters, and its length is 14 meters. The chamber is planned to be equipped with unique systems for high-efficiency vacuum pumping and heat removal. These systems make it possible to create space-like conditions.

A plasma electric rocket engine based on a magnetic plasma accelerator (MPA) uses magnetic and electric fields to accelerate plasma—ionized propellant gas (such as xenon, argon, or hydrogen) composed of charged particles such as ions and electrons to generate thrust.

The MPA uses a combination of magnetic and electric fields to manipulate and accelerate the plasma. Generated by coils or permanent magnets, the magnetic field confines and directs the plasma. Applied across electrodes or induced by the system, the electric field accelerates the charged particles. In some designs, this is done via the Lorentz force, where the interaction of electric current and magnetic field drives the plasma.

Variants of these engines such as the Magnetoplasmadynamic (MPD) have been tested in labs and prototypes (e.g., NASA’s X3 thruster, a related concept). The VASIMR (Variable Specific Impulse Magnetoplasma Rocket), developed by Ad Astra Rocket is another example, using RF heating and magnetic confinement to achieve variable thrust and efficiency.