Fatima Ebrahimi, a researcher at the Princeton Plasma Physics Laboratory at the U.S. Department of Energy, has developed a new type of thruster that will allow humans to explore space in the future. The new thruster uses magnetic fields to release plasma particles from the back of a rocket that propels the spacecraft. Plasma is the fourth state of matter and is an electrically charged gas.
The concept accelerates the particles using magnetic reconnection, a natural process found throughout the universe, including the surface of the sun. Magnetic reconnection is when magnetic field lines merge, suddenly separate, and then merge again, producing significant amounts of energy. The researcher said she had been working on the concept for a while, and the original idea came back in 2017.
The idea came to her while she was sitting on a deck thinking about the similarities between the car’s exhaust and the high-velocity exhaust particles created by the National Spherical Taurus Experiment in the lab. During the operation, the tokamak produces magnetic bubbles called plasmoids at a speed of about 20 kilometers per second. Ebrahimi says that was a lot like a thrust to her.
Current plasma thrusters use electric fields to propel particles and can only produce a low specific velocity. Computer simulations performed on computers in the laboratory show that the new plasma thruster concept can generate exhaust gases at speeds of hundreds of kilometers per second, which is ten times faster than the other thrusters.
The speed of the plaster at the start of the spacecraft’s journey can bring outer planets within reach of astronauts, reducing the time it takes to travel long distances. The new thruster has higher strength magnetic fields that can increase or decrease the amount of thrust, allowing for fine tuning of the speed. The thruster also ejects both plasma particles and plasmoids, the latter adding force to propulsion. The new thruster can also consist of heavy or light atoms, allowing the thrust to be tailored to the mission.