Science

To Mars and beyond

Space travel may soon be revolutionized with EmDrive

Space –a vestige of the universe that continues to escape the understanding of science’s greatest minds. Beyond satellite images and deep space photos, we have next to no knowledge of what actually lies beyond our planet. With the current level of technological advancement in spacecrafts, it would be nearly impossible to reach any planet further than Mars in a reasonable time. The other reason for our lack of space exploration is the copious amount of liquid hydrogen necessary for long stellar travel. However, this could all be changing.

In 2001, aerospace engineer Roger Shawyer designed the EmDrive with the intention of replacing the current engines NASA uses. The technology is essentially a propulsion system that does not use propellant for locomotive motion. This would remove the need for any sort of liquid or gaseous fuel thus making the vessel significantly lighter and increasing its manoeuvrability. These are not the only drastic improvements to spacecrafts that these engines would bring. The speeds it would be able to achieve would greatly outstrip our current engines. In theory, this sounds like an unbelievable advancement of space technology. However, there are certain issues with the EmDrive that can’t be overlooked as they contradict some governing laws of the universe.

Newton’s third law states that for every action, there is an equal and opposite reaction. For example, in a conventional engine, fuel is ignited and mass is propelled outwards creating an opposite force. The EmDrive is known as a reactionless drive because it lacks the reaction that is defined by Newton’s law in being a locomotive engine, yet having no external force acting on it.

unspecifiedIn essence, the EmDrive is an impossibility according to classical Newtonian physics. Despite this insurmountable issue, NASA and independent Chinese researchers continued to research and test the capabilities of this idea. At first, Shawyer managed to produce 0.016 newtons of force using only 850 watts of electricity with 45000 pounds granted by the British Government. While this does seem like the smallest of victories, it is actually an almost preposterous discovery that many in the field doubted. To give an example as to the scale of this finding, using an EmDrive would be similar to blowing on your own sail and expecting your boat to travel forwards.

Further tests by Chinese scientists and a group within NASA yielded numbers much smaller than those of Shawyer, but they still showed the same signs of victory. Shawyer even suggested that when he tested his version of the drive, he opened a “warp bubble” that allowed the EmDrive to transport itself.

Now, before all of the Trekkies out there get excited, it’s almost certain that this did not in fact happen and we won’t be telling Mr. Sulu to go warp speed anytime soon. While these bold and frankly ridiculous claims do little to paint Shawyer as a reliable scientist, a paper he wrote on the subject of the actual drive is being peer reviewed as we speak. The success of this review will determine whether the EmDrive that Shawyer invented is a viable engine or a dud.

While Shawyer believes that the reactionless engine can work within our current laws of physics, another physicist named Michael McCulloch has come up with an explanation that may fall well outside of our understanding of physics. The research from the Plymouth University professor has to do with something called the Unruh effect. This is an extremely complicated concept that is predicted by relativity and simply put, makes the universe appear hotter the more you accelerate. This concept is unconfirmed as of now, but does fit within our current understanding. This theory predicts that particles form in the vacuum of space from the heat of the universe accelerating. The one exception is the acceleration observed with the EmDrive tests, which is not yet within our understanding of the universe. This unknown acceleration could be explained by the Unruh particles that have smaller wavelengths during acceleration. These different sized wave-lengths would fit into either end of the cone like structure and bounce around to change inertia and create thrust.

To someone who doesn’t have a deep knowledge of theoretical physics, this could seem ridiculously overwhelming. But McCulloch’s paper makes little sense even to many established physicists. However, how it works shouldn’t be the main concern. The concern should be whether he’s right –and if he is, then the EmDrive is plausible even with its seemingly universe breaking physics.

Why does any of this matter, and what tangible good can the EmDrive contrib-ute to our understanding of space? It is theorized that this new engine could be used in cars and even some satellites, but the real draw is the potential for space travel. The possible speeds that this drive could reach would allow a spacecraft to reach the Moon in a matter of hours, Mars in months, and possibly even Pluto in as little as two years. This may sound slightly optimistic, but if the EmDrive turns out to be a usable piece of technology, these speeds are well within the realm of possibility. For organizations such as NASA, SpaceX and others, costs would go down with a lighter weight craft that has no need for heavy fuel canisters.

For now, the only thing proven is that different tests have come to the same conclusion- the EmDrive is a possibility. The lack of definitive results is the only thing keeping this myth from becoming reality. And if everything goes according to Shawyer’s most ideal plans, the EmDrive will become a staple for all space organizations around the world.

Images courtesy of Benjamin Lappalainen

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