MIT Develops Revolutionary Spacecraft Engine Using Single Fuel for Chemical and Electric Propulsion

Massachusetts Institute of Technology researchers have achieved a major breakthrough in spacecraft propulsion by developing a system that uses a single fuel to power both chemical and electric thrusters. The innovation could revolutionize small satellite missions by providing unprecedented flexibility in space maneuvers, combining the rapid acceleration capabilities of chemical rockets with the fuel efficiency of electric propulsion. The technology addresses a long-standing challenge in the aerospace industry, where spacecraft typically require separate fuel systems and hardware for different types of propulsion, adding weight and complexity to missions.

The research, led by former MIT postdoctoral researcher Amelia Bruno and published in the Journal of Propulsion and Power, demonstrates that a "green monopropellant" originally developed by the U.S. Air Force can successfully power both chemical thrusters and miniature electric thrusters called electrospray thrusters. "If you can have chemical and electrical propulsion in one small package, it's the best of both worlds," Bruno explained. "This opens the door for small satellites to do even more science, more observations, and more interesting missions, all on a smaller and cheaper platform."

Electrospray thrusters, roughly the size of a dime, use electric fields to charge particles in liquid propellant and eject them into space, creating thrust. These systems are extremely fuel-efficient and well-suited for gradual, precise maneuvers such as slowly pushing spacecraft through long interplanetary journeys. Chemical thrusters, by contrast, deliver powerful bursts of thrust that allow spacecraft to quickly accelerate, decelerate, or change position. By identifying a propellant capable of powering both systems, MIT researchers believe they can significantly expand the capabilities of small satellites without the traditional weight and complexity penalties.

The breakthrough is being tested through NASA's Green Propulsion Dual Mode mission, featuring a briefcase-sized CubeSat equipped with one chemical thruster and four electrospray thrusters, all drawing fuel from a single tank. This represents the first attempt to test dual-mode propulsion on a small spacecraft. Study co-author Paulo Lozano, the Miguel Alemán Velasco Professor of Aeronautics and Astronautics at MIT, envisions dramatic possibilities for the technology. "We could send CubeSats to Mars, or the asteroid belt, where they could make the journey slowly, using electrospray thrusters," he said. "You could then use your chemical thrusters to quickly move to look at interesting features."

The implications of this technology extend far beyond current CubeSat capabilities, potentially enabling small satellites to undertake ambitious deep space missions previously reserved for much larger and more expensive spacecraft. The ability to efficiently travel long distances using electric propulsion while retaining the capability for rapid maneuvers through chemical propulsion could transform how scientists approach planetary exploration, asteroid mining, and other space-based research. As the space industry continues to move toward smaller, more cost-effective missions, this dual-mode propulsion system could become a game-changing technology for the next generation of space exploration.