In rocket VASIMR magnetic fields emanating from the plasma loaded back of engine, creating a pulse in the opposite direction.
Ad Astra Rocket Company tested the most powerful plasma rocket so far in the world. The company announced that the rocket engine VASIMR VX-200 showed power 201 kilowatts in a vacuum chamber, overcoming the fundamental barrier of 200 kW in the first test.
„This is the most powerful plasma rocket in the world today,“ said Franklin Chang–Diaz, a former astronaut by NASA and CEO of Ad Astra Rocket Company. The company signed an agreement with NASA to test the 200-kilowatt VASIMR engine on the International Space Station in 2013. The engine is capable of providing periodic accelerations to maneuver the station to maintain the desired height (the orbit of the ISS continuously falling due to air resistance). Acceleration space station currently provide spacecraft with conventional engines that consume about seven and a half tons of fuel per year. Reducing the fuel with VASIMR to 0.3 tons, Chang–Diaz said, it would save NASA millions of dollars annually.
But the company has much more ambitious plans for his engine – such as high-speed mission to Mars. 10 and 20 megawatt VASIMR engine can deliver human crew to Mars only for thirty-nine days, while traditional rockets can do this for six months or more. Less travel time means that astronauts would be less exposed to cosmic radiation, which is a serious problem for missions to Mars.