Mendalla
Happy headbanging ape!!
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I have been recently following the saga of the EM Drive, a possible new propulsion system for spacecraft. It is not powerful, but has one big advantage over many current systems: no need for a fuel tank so the spacecraft being propelled can have a much lower mass, which helps make up for the drive's lack of thrust relative to traditional rockets.
However, what makes it unique also makes it controversial. A normal spacecraft engines like the familiar rocket, as well as less familiar ones like ion and plasma drives, all require some kind of exhaust. Under Newton's third law of motion, "for every action there is an equal and opposite reaction", the exhaust shooting out of the engine one way (the action) produces a counter force that pushes the spacecraft in the opposite direction (the reaction). Which ends up looking something like this:
EM Drive doesn't do this. It consists of microwaves bouncing around in a closed, conical chamber. Under normal physics, this should simply not work. However, in test after test, including a paper by a NASA that recently passed peer-review, it has been shown to generate a small amount of thrust. Nowhere near as powerful as a rocket or even an ion drive, but enough to be potentially useful if you pump enough power into it. Since no fuel is burned to produce exhaust, no huge fuel tank is needed, just a power source like a nuclear reactor or solar panels, which most spacecraft have to carry anyhow to power computers, sensors, cameras, and so on. Why it works remains unclear, but there are some possibilities in the weird world of quantum physics.
This means that there is no blast of fire, no loud roar, no wild crazy ride, just a nice, steady push. It cannnot, as currently understood, generate enough thrust to use for launches from Earth (i.e. it is not powerful enough to overcome our planet's gravity), but potentially enough to use in deep space, e.g. for going to Mars and beyond. And it produces more thrust than other "reactionless" options like solar sails, which are also currently undergoing testing so might push those aside for some applications.
So where does EM Drive go from here? Well, many in the science community remain skeptical, pointing out possible causes of the "thrust" other than the drive itself, basically saying that the positive results so far are errors. The root problem is that it seems to violate conservation of energy in bypassing Newton's third law.
Next step is going to be to launch one into space and try it in freefall with no air, removing some possible sources of error which also serves as a proof of concept of whether it really can be used to propel spacecraft.
I'll try to pop in here from time to time with updates and more cool SCIENCE! and others are welcome to add their cool SCIENCE! stuff.
For more information:
http://www.sciencealert.com/it-s-of...wed-em-drive-paper-has-finally-been-published
https://en.wikipedia.org/wiki/RF_resonant_cavity_thruster
However, what makes it unique also makes it controversial. A normal spacecraft engines like the familiar rocket, as well as less familiar ones like ion and plasma drives, all require some kind of exhaust. Under Newton's third law of motion, "for every action there is an equal and opposite reaction", the exhaust shooting out of the engine one way (the action) produces a counter force that pushes the spacecraft in the opposite direction (the reaction). Which ends up looking something like this:
EM Drive doesn't do this. It consists of microwaves bouncing around in a closed, conical chamber. Under normal physics, this should simply not work. However, in test after test, including a paper by a NASA that recently passed peer-review, it has been shown to generate a small amount of thrust. Nowhere near as powerful as a rocket or even an ion drive, but enough to be potentially useful if you pump enough power into it. Since no fuel is burned to produce exhaust, no huge fuel tank is needed, just a power source like a nuclear reactor or solar panels, which most spacecraft have to carry anyhow to power computers, sensors, cameras, and so on. Why it works remains unclear, but there are some possibilities in the weird world of quantum physics.
This means that there is no blast of fire, no loud roar, no wild crazy ride, just a nice, steady push. It cannnot, as currently understood, generate enough thrust to use for launches from Earth (i.e. it is not powerful enough to overcome our planet's gravity), but potentially enough to use in deep space, e.g. for going to Mars and beyond. And it produces more thrust than other "reactionless" options like solar sails, which are also currently undergoing testing so might push those aside for some applications.
So where does EM Drive go from here? Well, many in the science community remain skeptical, pointing out possible causes of the "thrust" other than the drive itself, basically saying that the positive results so far are errors. The root problem is that it seems to violate conservation of energy in bypassing Newton's third law.
Next step is going to be to launch one into space and try it in freefall with no air, removing some possible sources of error which also serves as a proof of concept of whether it really can be used to propel spacecraft.
I'll try to pop in here from time to time with updates and more cool SCIENCE! and others are welcome to add their cool SCIENCE! stuff.
For more information:
http://www.sciencealert.com/it-s-of...wed-em-drive-paper-has-finally-been-published
https://en.wikipedia.org/wiki/RF_resonant_cavity_thruster
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