VASIMR-powered spacecraft "space plasm rockets"

During more than 40 years of spaceflight, a lot of things have changed. Today’s Space Shuttle is a luxury ship compared to the Mercury capsules that carried the first American astronauts into space. Forty years ago, a lot of people might have had a hard time believing that Americans and Russians would be living together in space on one Space Station. Space probes have visited every planet except Pluto, and a mission there is currently being planned. One thing that has changed very little, however, is the way rockets work. While different fuels have been used, and current rocket engines are more high-tech than their early predecessors, the basic concepts involved are basically the same. But, NASA researchers are currently working on a way to change that, as VASIMR is a plasma-based propulsion system. An electric power source is used to ionize fuel into plasma. Electric fields heat and accelerate the plasma while the magnetic fields direct the plasma in the proper direction as it is ejected from the engine, creating thrust for the spacecraft. The engine can even vary the amount of thrust generated, allowing it to increase or decrease its acceleration. It even features an “afterburner” mode that sacrifices fuel efficiency for additional speed. Possible fuels for the VASIMR engine could include hydrogen, helium, and deuterium.