A new concept for rockets uses the mechanism behind solar flares

A new type of rocket propeller that could take humanity to Mars and beyond was proposed by a physicist at the US Department of Energy’s Princeton Plasma Physics Laboratory (PPPL).

The device will apply magnetic fields to cause particles of plasma, electrically charged gas, also known as the fourth state of matter, to shoot out the back of a rocket and, due to the retention of momentum, move the vessel forward. drive. Current space-saving plasma thrusters use electric fields to propel the particles.

The new concept will accelerate the particles using magnetic reconnection, a process found throughout the universe, including the surface of the sun, in which magnetic field lines converge, suddenly separate and then reassemble, producing much energy. Recoupling also occurs in donut-shaped fusion devices known as tokamax.

“I’ve been cooking this concept for a while now,” said the PPPL’s ​​lead researcher, physical scientist Fatima Ebrahimi, the inventor of the concept and author of an article in which the idea in the Journal of Plasma Physics. ‘I had the idea in 2017 while sitting on a deck thinking about the similarities between a car’s exhaust and the high-speed exhaust particles created by PPPL’s ​​National Spherical Torus Experiment (NSTX),’ the forerunner of the current flagship fusion facility in the laboratory. “During its action, these tokamak produce magnetic bubbles, called plasmids, that move about 20 kilometers per second, which to me looks a lot like shock.”

Fusion, the force that drives the sun and stars, combines light elements in the form of plasma – the warm, charged state of matter made up of free electrons and atomic nuclei that represent 99% of the visible universe – to generate massive amounts of energy wake. Scientists are trying to repeat the merger on Earth for a virtually inexhaustible power supply to generate electricity.

Current plasma propellants that use electric fields to drive 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 for science user facilities at the Lawrence Berkeley National Laboratory in Berkeley, California, have shown that the new plasma thruster concept can generate exhaust fumes. with speeds of hundreds of kilometers per second, 10 times faster than those of other drivers.

The faster velocity at the start 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 vessel takes a while to speed up,” she said. “But if we make propellers based on magnetic reconnection, we can conceivably complete long-distance transmissions in a shorter period of time.”

There are three main differences between Ebrahimi’s screw concept and other devices. The first is that changing the strength of the magnetic fields can increase or decrease the amount of impact. “By using more electromagnets and more magnetic fields, you can actually turn a knob to refine the velocity,” Ebrahimi said.

Second, the new screw produces motion by ejecting both plasma particles and magnetic bubbles known as plasmoids. The plasmids give power to the propulsion, and no other thrust concept contains it.

Third, unlike current screw concepts that rely on electric fields, the magnetic fields in Ebrahimi’s concept allow the plasma in the screw to consist of heavy or light atoms. This flexibility allows scientists to adjust the amount of driving force for a specific mission. “While other drivers require heavy gas, made from atoms like xenon, you can use any type of gas you want in this concept,” Ebrahimi said. In some cases, scientists prefer light gases because the smaller atoms can move faster.

This concept broadens PPPL’s ​​portfolio of space propulsion research. Other projects include the Hall Thruster Experiment started in 1999 by PPPL physicists Yevgeny Raitses and Nathaniel Fisch to investigate the use of plasma particles for moving spacecraft. Raitses and students are also investigating the use of small Hall propellers to give small satellites called CubeSats greater mobility as they orbit the earth.

Ebrahimi emphasized that her screw concept stems directly from her research on fusion energy. “This work was inspired by mergers from the past and is the first time that plasmoids and reconnection for space propulsion have been proposed,” Ebrahimi said. “The next step is to build a prototype!”