Dr Fatima Brahimi has created a new concept for fusion missiles that could propel humans to Mars and beyond.
A physicist at the U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) has designed the rocket that will use magnetic fields to launch plasma particles – electrically charged gas – into a vacuum of space.
According to Newton’s second and third laws of motion, maintaining momentum means pushing the missile forward – and at speeds ten times faster than similar devices.
While current space-proven plasma propulsion motors use electric fields to propel particles, the new missile design will accelerate them using magnetic reconnection.
This process is found throughout the universe but is most noticeable to humanity on the surface of the sun. When magnetic field lines converge there, before disconnecting and then reconnecting again, it produces an enormous amount of energy.
Similar energy is produced inside ring-shaped machines known as tokamaks, a magnetic confinement device that is also a prime candidate for a practical nuclear fusion reactor.
“I’ve been cooking this concept for a while,” said lead research physicist at PPPL, Dr. Fatima Ibrahimi, who has published her paper detailing the invention in the journal Plasma Physics.
“The idea came to me in 2017 when I was sitting on the deck and thinking about the similarities between the car exhaust and the high-speed exhaust particles generated by the National Globe Ring (NSTX) experiment from PPPL,” she said.
NSTX is the flagship of the laboratory’s current major fusion facility, which is being investigated with funding from the US Department of Energy.
Dr. Ibrahimi added, “While operating, this tokamak produces magnetic bubbles called plasmids moving at about 20 kilometers per second, which seemed to me a lot like a thrust.”
Nuclear fusion is the force that moves the sun and stars. It combines the light elements in the form of plasma – the hot, charged state of matter made up of free electrons and an atomic nucleus representing 99% of the visible universe – to generate enormous amounts of energy.
If a reactor could be reconstructed operating on the same principles on the ground, it would provide an “almost inexhaustible supply of energy for electricity generation” according to PPPl.
Dr. Brahimi’s new concept delivers significantly better performance than the plasma propulsion engines found in computer simulations – generating exhaust at speeds of up to hundreds of kilometers per second, ten times faster than other propulsion engines.
The physicist said that this faster speed at the start of the spacecraft’s flight could make exoplanets within reach of astronauts.
“Long-distance travel takes months or years because the specific thrust of chemical rocket engines is very low, so the vehicle takes some time to reach speed,” she said.
“But if we built thrusters based on magnetic reconnection, then we could complete long-range missions in a shorter period of time.”
She asserted that her concept of motivation stems directly from her research into fusion energy. “This work is inspired by previous fusion work and this is the first time that the use of plasmids and reconnection for space propulsion has been proposed,” said Dr. Ibrahimi. “The next step is to build a prototype!”