NASA announced that it had tested a theoretical engine, known as the EmDrive, that could open up the door for interplanetary exploration. This new propulsion system, which is still in its very early stages of development, doesn't use any type of traditional fuel to power an engine. Instead, it uses directed microwaves to create thrust, although scientists still aren't exactly sure how – or even why – the EmDrive works.
This new type of engine is the brain child of a man named Guido Fetta, who calls his creation the Cannae Drive. Fetta, who is not a theoretical physicist, and only holds a degree in Chemical Engineering, has been pitching the idea for a few years, but saw many scientists dismiss his work out of hand, as it seems to defy the laws of physics. But teams of scientists in both China and Argentina have been able to replicate his work, which seems to violate the rules of conservation of momentum.
What makes the Cannae Drive and EmDrive so special is that the lack of need for traditional fuels greatly cuts down on the weight of the engine, and the craft that it will power. It also means that without the worry of running out of fuel, the drive could greatly cut down on the amount of time that it will take to travel through space. For instance, under traditional rocket systems that we use now, it would take roughly six months or more to travel to Mars. But with a propulsion system such as this one, that same journey could be reduced to just a few weeks.
Obviously there is a lot of work that needs to be done before we will see the EmDrive actually implemented, but this preliminary work looks very promising. The systems that NASA developed are on an incredibly small scale, and even though they shouldn't work, they have been able to produce small amounts of thrust. Further research into this discovery will need to be made, and scaling the engine up to a useful, efficient, size will take likely take years. But still, this is a major step forward to solving one of our problems with long distance space travel, and a huge leap towards the potential for exploring our solar system, and beyond.