Dr. Fatima Ebrahimi has invented a new fusion rocket that could one day take humans to Mars
Dr. Fatima Ebrahimi, who works for the US Department of Energy’s Princeton Plasma Physics Laboratory (PPPL), has invented a new fusion rocket that could one day take humans to Mars.
The device uses magnetic fields to shoot plasma particles from the back of the rocket and propel the craft through space.
Using magnetic fields allows scientists to tailor the amount of thrust for a particular mission and astronauts change the amount of thrust while piloting to distant worlds.
Ebrahimi’s innovation would also take space fairing heroes to the Red Planet 10 times faster than current rocket thrusters that use electric fields to propel the particles.
‘I’ve been cooking this concept for a while,’ said Ebrahimi.
‘I had the idea in 2017 while sitting on a deck and thinking about the similarities between a car’s exhaust and the high-velocity exhaust particles.’
‘During its operation, this tokamak produces magnetic bubbles called plasmoids that move at around 20 kilometers per second, which seemed to me a lot like thrust.’
Fusion is the power that drives the sun and stars, and combines light elements in the form of plasma.
The device uses magnetic fields to shoot plasma particles from the back of the rocket and propel the craft through space
Plasma is the hot, charged state of matter composed of free electrons and atomic nuclei that represents 99 percent of the visible universe – and is capable of generating massive amounts of energy.
Scientists have been working around the clock to replicate fusion in a lab with the hopes of harnessing its power to produce electricity for rockets traveling through deep space.
Current plasma thrusters that use electric fields to propel the particles can only produce low specific impulse, or speed.
But computer simulations performed on PPPL computers and the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility at Lawrence Berkeley National Laboratory in Berkeley, California, showed that the new plasma thruster concept can generate exhaust with velocities of hundreds of kilometers per second, 10 times faster than those of other thrusters.
That faster velocity at the beginning of a spacecraft’s journey could bring the outer planets within reach of astronauts, Ebrahimi said.
‘Long-distance travel takes months or years because the specific impulse of chemical rocket engines is very low, so the craft takes a while to get up to speed,’ she said.
Using magnetic fields allows scientists to tailor the amount of thrust for a particular mission and astronauts change the amount of thrust while piloting to distant worlds.
‘But if we make thrusters based on magnetic reconnection, then we could conceivably complete long-distance missions in a shorter period of time.’
Although using fusion to power rockets is not a new concept, Ebrahimi’s thruster differ from leading devices in three ways.
The first is that changing the strength of the magnetic fields can increase or decrease the amount of thrust, which will allow better maneuvering through the dark abyss that is space.
‘By using more electromagnets and more magnetic fields, you can in effect turn a knob to fine-tune the velocity,’ Ebrahimi said.
Second, the new thruster produces movement by ejecting both plasma particles and magnetic bubbles known as plasmoids.
The plasmoids add power to the propulsion and no other thruster concept incorporates them.
However, the last difference between Ebrahimi’s concept and other ones is that hers uses magnetic fields to shoot particles of plasma out from the back of the rocket – space-proven devices using electric fields.
Using magnetic fields may be a game changer, as It allows scientists to tailor the amount of thrust for a particular mission.
‘While other thrusters require heavy gas, made of atoms like xenon, in this concept you can use any type of gas you want,’ Ebrahimi said. Scientists might prefer light gas in some cases because the smaller atoms can get moving more quickly.
