The origins of Ion Thruster technology date back to 1930, when Dr. Wernher von Braun, a German rocket scientist, was introduced to the possibility of electric propulsion by his mentor, Dr. Hermann Oberth. Unfortunately, von Braun initially underestimated its potential and preferred to specialize in chemical propulsion systems.
After World War II, von Braun and hundreds of other German rocket experts surrendered to the Americans. After that they were sent to Fort Bliss, Texas, to develop rocket technology for the U.S. Army Research. Although von Braun worked in the military field, his great dream was to develop a rocket that could reach other planets.
Thinking about that ideal, von Braun met Ernst Stuhlinger, a member of the original German team that developed the first rockets in the world. He recovered the ideas of his mentor, Professor Oberth, and both agreed that electric propulsion might be a viable solution to reach Mars. In this way, Stuhlinger focused on the theory of electric propulsion. His studies culminated in the presentation of a work entitled 'Possibilities of the Electric Propulsion of Spaceships', in which he demonstrated that this system was much more efficient than one of chemical propulsion. Its impact was enormous among the scientific community and would eventually lead to the idea of developing Ion Engines...
What is the Ion thrust?
An ion thruster is an electric propulsion system, designed for space vehicles, which creates an impulse by accelerating ions. In practice, this term is used to refer to all electric propulsion systems that accelerate plasma, since it consists of ions. Depending on how the ions accelerate, these thrusters can be categorized differently. For one side, those who use electrostatic force, using the Coulomb force. On the other hand, those that use the electromagnetic force thanks to the Lorentz force.
Compared to chemical rockets, ion thrusters have less direct thrust, but are capable of reaching higher speeds thanks to their higher performance and efficiency. This is especially noticeable for long journeys where the chemical systems gain a lot with a much lower power consumption.
NASA has been the great promoter of this propulsion system. Being the Deep Space 1 probe, launched in 1998, the first to have an ion engine to reach another planetary body. Has been joined by the European Space Agency (ESA) and the Japanese Space Agency, which have used it in different satellites and spacecraft.
After the great strategic alliance of NASA and ESA to develop a new generation of space shuttles at the European Aerospace Center in Seville, many are the experts who believe that ion thrusters will play a very important role in this new generation. Especially, after the recent advances in systems powered by nuclear energy and the theoretical studies for the use of hydrogen fusion technology. Although according to experts there are still many years left to see a real practical application. No matter how long it takes, it’s clear that ion engines will be the keystone of the 21st century space race.