New NASA Space Engine Defies Physics
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The internet buzzed recently with news that NASA is developing a Star Trek-like warp drive engine. That sounded neat, so I checked it out. It turns out we are not ready to fold space, but we may be a hair closer -- by developing new kinds of propulsion systems. To learn more,
I spoke with Jonathan Ward, Volunteer NASA JPL Solar System ambassador, and author of two forthcoming books about the Apollo Space missions.
One recent concept that NASA’s been trying out is called the ion engine, and rather than mixing chemicals propellants together, it uses an inert gas as a propellant.
At a cost of around $13,000 per pound, one of the challenges we face getting off the earth is weight. Traditional chemical fuel is heavy, but a gas, like xenon, for example, is much lighter. According to Newton's third law, every action has an equal and opposite reaction. To propel the spacecraft, the ion engine basically strips the electrons off of the gas atoms and shoots the now electrically charged atoms, called ions, out the back at the speed of light.
The advantage of this kind of engine is that it uses a lot less fuel then the typical type of chemical engine. But the disadvantage is that the thrust is very, very small. The pressure exerted is about the same as a piece of paper sitting on your hand but if you keep that small pressure up for weeks or months at a time, you can actually accelerate the spacecraft to thousands of miles an hour.
This type of engine is being used successfully on the Dawn space probe, currently orbiting the dwarf planet Ceres in the asteroid belt. But lately we are hearing of a newer propulsion system. It’s not warp drive, the internet got that wrong if you can believe it. But it’s intriguing because it should be impossible, according to physics.
They claimed in 2010 to have come up with an engine that burns absolutely no fuel and has no moving parts whatsoever. The new engine is called the Em Drive. It uses the concept of radiation pressure that light or radio waves do exert a small amount of pressure on an object when it's in space. So, what’s different about the Em Drive is that it generates this radiation pressure inside its engine. Very simply, it has a microwave generator like you would have in a microwave oven. It generates these high energy microwaves into a metallic cone-shaped cavity. The Em Drive’s inventor, Roger Shawyer, claims that the microwaves produce a small amount of thrust because of the way they bounce around inside that chamber. On the face of it, the Em Drive completely violates the laws of conservation of momentum, one of the basic laws of physics. It’s a closed system, nothing is going in or out. The only thing that's going on is the microwaves are bouncing around inside. So, theoretically there should be no motion generated by this whatsoever.
If the Em Drive defies physics, what exactly is going on here?
Shawyer claims that Newton’s laws don’t apply in this case here. He thinks there are other factors that are going on at a smaller micro, micro, microscopic level that we don’t understand fully.
At the subatomic level classical physics fails. That’s where Quantum physics, the physics of the very, very small, takes over.
What if this Em Drive does in fact work? It would really be a game changer. So, imagine space flight or air travel where you don’t need to carry any fuel with you. All you need is electricity to power the Em Drive. Eliminating the fuel requirements for satellites, that could reduce launch costs tremendously. And the useful life-span a communications satellite could go up to about 30 years without having to worry about the fuel being burned up on board. Lower cost for satellites, more satellites for Earth-resource management and things like that.
The force generated by the Em-Drive is so tiny that there is a possibility the measurements were wrong.
It’s been published, but it hasn’t been peer reviewed. NASA, in fact, wants there to be an independent validation at another facility. But again, what’s intriguing is that the preliminary results are that this Cannae drive, or the Em Drive, does indeed produce a thrust, if in fact it’s not due to experimental error. There is something going on that we can’t explain using conventional physics. They talk about interactions with the quantum vacuum plasma, which is a lot deeper than I was able to understand after several years of physics in college.