A researcher from the US Department of Energy’s Princeton Plasma Physics Laboratory named Fatima Ebrahimi has developed a new type of thruster that could help humans explore space in the future. The new thruster uses magnetic fields to cause plasma particles to shoot out of the back of a rocket propelling the spacecraft forward. 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 sun’s surface. Magnetic reconnection is when magnetic field lines converge, suddenly separate, and then rejoin, producing significant amounts of energy. The researcher said that she had been working on the concept for a while, with the original idea coming back in 2017.
The idea came to her while 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 at the laboratory. During the operation, the tokamak produces magnetic bubbles called plasmoids, moving at about 20 kilometers per second. Ebrahimi says that seemed a lot like thrust to her.
Current plasma thrusters use electric fields to propel particles and are only able to produce low specific speed. Computer simulations performed at computers in the laboratory show that the new plasma thruster concept can generate exhaust with velocities of hundreds of kilometers per second, which is ten times faster than the other thrusters.
The plaster velocity at the beginning of the spacecraft’s journey could bring the outer planets within reach of astronauts leading to long-distance space travel taking less time. The new thruster has higher strength magnetic fields that can increase or decrease the amount of thrust, allowing fine-tuning of the velocity. The thruster also ejects both plasma particles and plasmoids, with the latter adding power to the propulsion. The new thruster can also consist of heavy or light atoms allowing thrust to be tailored for the mission.