The EM Drive: The Future Of Space Travel

[Twiggy 2,966]

The EM drive, thought to be impossible as it seems to defy Newton's third law, has recently been proven to work.

 

Instead of using heavy, inefficient rocket fuel, it bounces microwaves back and forth inside a cone-shaped metal cavity to generate thrust. According to the calculations of the man who came up with the concept, the EM Drive could be so efficient that it could power us to Mars in just 70 days.

 

http://www.sciencealert.com/it-s-official-nasa-s-peer-reviewed-em-drive-paper-has-finally-been-published

 

I am super hype for what this means for our ability to explore our solar system. We'll finally make it to Mars, at least. All we need to do now is to get shipyards to start building with a more Gothic aesthetic, and we're finally in business.

 

The Emperor protects.

 

[Blackshirt Brony 415]

The data doesn't appear to be conclusive, and was allegedly too marginal for experts to jump to any conclusions.¹ That said, this was still a spooky experiment and this design will give a lot of people headaches if it holds up (I'm still skeptical).

 

I prefer Hawking radiation personally.

 

 

 

1.

 

http://www.forbes.com/sites/startswithabang/2016/09/02/nasas-impossible-space-engine-the-emdrive-passes-peer-review/#7b49823692c5

 

EDIT: Apparently I was reading an old article and how does that thing even work I don't understand

Edited November 22, 2016 by Blackshirt Brony

[Twilight Dirac 721]

What is really interesting about this experiment is it has potential to invalidate Newton's Third law of motion, which would really shake up our understanding of physics.  But like Blackshirt Brony, I remain skeptical about that claim.

 

Do note that the actual prototype is a rather crap engine even if you do not require a propellant.  The thing still only produces around a milliNewton of thrust when consuming 1 kW of power, so you would need 5 MW of power to generate a single pound of thrust.  Maybe if you brought a nuclear reactor into orbit with it, but you would probably be better off with something like a VASIMR if you were going that route.  The main problem with space travel remains escaping Earth's gravity in any case.

Edited November 22, 2016 by Twilight Dirac

[I used to be a stranger 7,993]

The EM drive, thought to be impossible as it seems to defy Newton's third law, has recently been proven to work.

 

Instead of using heavy, inefficient rocket fuel, it bounces microwaves back and forth inside a cone-shaped metal cavity to generate thrust. According to the calculations of the man who came up with the concept, the EM Drive could be so efficient that it could power us to Mars in just 70 days.

 

The actual thing that's making the rounds on news is that the PhD thesis submitted for peer review has passed its first round. That means that relevant experts are assenting that the method used to test it is valid, but it has still yet to be determined if the device actually does anything.

 

That said, I'd be willing to see if they show a new fundamental understanding of physics.

 

But it's starting to annoy me how stories about the EM drive make their rounds on social media. Everyone loves an underdog but the nearly conspiratorial interest lay-space enthusiasts on the internet seems to have about this technology can be rather exasperating.

 

• 1mN of thrust is a terrible trade-off for 1kW of energy. While this thrust level is better than photon thrusters (aka solar sails or flashlights), Ion Engines can produce far more thrust per time (~25km/s per year versus ~8km/s per year), and photon thrusters have a specific impulse of lightspeed. It would take a LOT of optimization to bring a nascent and exotic technology like the EM drive to hold a candle to existing technology.
• The EM drive as far as we know it would just be another technology in a niche field which doesn't help us reach the stars much (yet). Even though ion engines are superior performance-wise right now, no one wants to get a satellite to Pluto in 80 years. They want it there NOW. Ion engines are efficient (EM drive less so) but their thrust is pathetic compared to conventional chemical propulsion.
• The proponents of the EM drive theorize that the force is coming from virtual particles drawn from the quantum vacuum state, but quantum physicists think that explanation is a load of bull. Hmm...

 

Some daunting problems to overcome.

 

And on the note of Delta-V: no you can't reach mars in 80 days with that. The advantage of Ion Engines and like technologies (such as the EM drive potentially) comes from their ability to burn efficiently for extremely long periods, not generating rapid thrust. An ion engine couldn't push away a piece of paper covering its thrust duct, but it could thrust with the force of milliNewtons for decades on a fuel tank the size of a pop bottle and not run out of fuel. A chemical rocket could produce a hundred tons of thrust but it would burn off an Olympic swimming pool out in a matter of seconds. In an application where time is not of the essence, the ion engine would always win in producing more thrust (eventually).

Edited November 22, 2016 by Blue

[Invincible 2,091]

Let's assume that the EM drive works. Even so, current models of physics can't seem to make good use of it. It's worth having it reviewed by experts, because of potential optimizations yet to be discovered. I suppose it has to show it works and demonstrate its effectiveness in scientific studies.

[TopQuark 409]

What is really interesting about this experiment is it has potential to invalidate Newton's Third law of motion, which would really shake up our understanding of physics.

 

Newton's Third Law is more flexible than many give it credit for, and I doubt having a thruster that doesn't use reation mass will change anything as major as that. You can propel yourself across the room in an office chair without expelling mass, just jiggling yourself back and forth. In this case, you're reacting against the force of friction of the ground. Newton's third law says that you just have to react against something, whether it be mass or an energy field. The Hubble space telescope doesn't break any physics just because it can use the magnetic field of the Earth to desaturate its reaction wheels without propellant.

 

 

Do note that the actual prototype is a rather crap engine even if you do not require a propellant.  The thing still only produces around a milliNewton of thrust when consuming 1 kW of power, so you would need 5 MW of power to generate a single pound of thrust.  Maybe if you brought a nuclear reactor into orbit with it, but you would probably be better off with something like a VASIMR if you were going that route.  The main problem with space travel remains escaping Earth's gravity in any case.

 

There have been no attempts to optimise the (really quite crude) prototype device, so there is no data on how much/little improvement in performance is gained from proper maufacture. Resonance cavities need to be extremely precise for optimal performance, so I imagine if the EM drive works, it can be improved quite a bit.

Edited November 23, 2016 by TopQuark

[EpicEnergy 23,173]

It's got to be the predecessor of the hyperdrive! We'll get there one day, I want to walk on the surface of Alpha Centauri or float in Jupiter's great red spot!

[Dreambiscuit 9,578]

Whether it works or not isn’t the main question here. Getting the powers-that-be off their brains and willing to take humanity a huge step forward is the main obstacle. And let’s face it, if technicians and politicians can stall until it becomes another generation’s problem, they will. We should have been on Mars by the mid 1970s, but by then the space race was winding down and we didn’t have the motivation to really kick ass in space.

If the technology works it would be the greatest thing in history. I personally love anything that kicks physics in the butt. There is no such thing as constant laws of science; we don’t have any idea the variables that exist beyond the scope of our own existence, and there’s always a fix for those who can think outside the box.