NASA confirms reactionless drive might be real

[Quantum Windbag]

This could be a game changer for inter system and interstellar travel.

Nasa is a major player in space science, so when a team from the agency this week presents evidence that "impossible" microwave thrusters seem to work, something strange is definitely going on. Either the results are completely wrong, or Nasa has confirmed a major breakthrough in space propulsion.
British scientist Roger Shawyer has been trying to interest people in his EmDrive for some years through his company SPR Ltd. Shawyer claims the EmDrive converts electric power into thrust, without the need for any propellant by bouncing microwaves around in a closed container. He has built a number of demonstration systems, but critics reject his relativity-based theory and insist that, according to the law of conservation of momentum, it cannot work.
According to good scientific practice, an independent third party needed to replicate Shawyer's results. As Wired.co.uk reported, this happened last year when a Chinese team built its own EmDrive and confirmed that it produced 720 mN (about 72 grams) of thrust, enough for a practical satellite thruster. Such a thruster could be powered by solar electricity, eliminating the need for the supply of propellant that occupies up to half the launch mass of many satellites. The Chinese work attracted little attention; it seems that nobody in the West believed in it.
However, a US scientist, Guido Fetta, has built his own propellant-less microwave thruster, and managed to persuade Nasa to test it out. The test results were presented on July 30 at the 50th Joint Propulsion Conference in Cleveland, Ohio. Astonishingly enough, they are positive.
The Nasa team based at the Johnson Space Centre gave its paper the title "Anomalous Thrust Production from an RF [radio frequency] Test Device Measured on a Low-Thrust Torsion Pendulum". The five researchers spent six days setting up test equipment followed by two days of experiments with various configurations. These tests included using a "null drive" similar to the live version but modified so it would not work, and using a device which would produce the same load on the apparatus to establish whether the effect might be produced by some effect unrelated to the actual drive. They also turned the drive around the other way to check whether that had any effect.

Nasa validates 'impossible' space drive (Wired UK)

 

[MaryL]

OK, I don't know anything about this EM drive, how long would it take to get from the earth to the moon using this drive? How is it comparable to the chemical reaction thrust engines used in space flight now? Horse power ratings, overall trust. As a concept, great. Is it practical, or will it every be practical?

 

[Quantum Windbag]

OK, I don't know anything about this EM drive, how long would it take to get from the earth to the moon using this drive? How is it comparable to the chemical reaction thrust engines used in space flight now? Horse power ratings, overall trust. As a concept, great. Is it practical, or will it every be practical?

If it actually turns out to work it will take a lot of experimentation to answer those questions.

 

[TheOldSchool]

I read that it could get us to Mars in weeks and potentially to the nearest star in 30 years. The key word there is POTENTIALLY! But man if this is the next revolution in space travel I hope I get to live to at least see the beginning of it.

 

[Steven_R]

This last line implies that the drive may work by pushing against the ghostly cloud of particles and anti-particles that are constantly popping into being and disappearing again in empty space.

If this is the case, then it really isn't a violation of conservation of momentum since Newton's Third Law of Motion is still in use. If I'm reading this right, effectively, this drive is pushing off those particles and anti-particles.

I looked at the paper and it's over my head, but based on my whopping 3/4 of a BS in physics eusa_shifty this doesn't seem to be all that out there.

 

[Quantum Windbag]

I read that it could get us to Mars in weeks and potentially to the nearest star in 30 years. The key word there is POTENTIALLY! But man if this is the next revolution in space travel I hope I get to live to at least see the beginning of it.

You aren't the only one.

 

[TheOldSchool]

I read that it could get us to Mars in weeks and potentially to the nearest star in 30 years. The key word there is POTENTIALLY! But man if this is the next revolution in space travel I hope I get to live to at least see the beginning of it.

You aren't the only one.

Sadly I imagine that even the first inklings of any serious engineering this technology would be over 50 years away

Add to that we haven't even developed a way to test if this would even be conceivable outside of a tiny scale. But DAMN if it doesn't sound awesome

 

[TheOldSchool]

I mean DAMN dumbed down it's pretty much like massive wireless energy across LIGHTYEARS! Go humans!

 

[Quantum Windbag]

I read that it could get us to Mars in weeks and potentially to the nearest star in 30 years. The key word there is POTENTIALLY! But man if this is the next revolution in space travel I hope I get to live to at least see the beginning of it.

You aren't the only one.

Sadly I imagine that even the first inklings of any serious engineering this technology would be over 50 years away

Add to that we haven't even developed a way to test if this would even be conceivable outside of a tiny scale. But DAMN if it doesn't sound awesome

I know, and my doctor doesn't think I have that much time left, but one can hope.

 

[TheOldSchool]

You aren't the only one.

Sadly I imagine that even the first inklings of any serious engineering this technology would be over 50 years away

Add to that we haven't even developed a way to test if this would even be conceivable outside of a tiny scale. But DAMN if it doesn't sound awesome

I know, and my doctor doesn't think I have that much time left, but one can hope.

Well hey cross your fingers that the medical community is working on some equivalently fantastic stuff

 

[Delta4Embassy]

Fascinating (raises an eyebrow.)

Don't need a lot of thrust for interstellar travel oweing to inertia and the frictionless nature of space, just a steady supply of it. Why ion engines are probably what we'll be looking at. Long duration, steady thrust. If this EM thing pans out it could be another ion-like solution.

 

[Moonglow]

I wonder how big of a magnetron the microwave emitter had??? I worked on ones at a Tyson's plant that were bigger than a double doored kitchen fridge..120 amps when the magnacore was at full capacity, make your hair stand on end....

 

[Vikrant]

The article was quite sensationalist and somewhat inaccurate. This idea of using electromagnetic wave as propulsion fuel in zero gravity or near zero gravity environment has been around since I was a kid and I am not exactly a young puppy.

First of all, you cannot bring an object in a state of rest to a state of motion without spending energy in the process. Similarly, you cannot bring an object in a state of motion to a state of rest without spending energy. For example, a spacecraft on its way to Mars spends considerable amount of fuel when it transitions itself from heliocentric orbit to the orbit of Mars. Why? Because the spacecraft is traveling at a very high velocity (well over a million KM per day) and it needs to slow down so that it can be arrested by Mars's gravitational field or it will escape and continue on its heliocentric path. It cannot slow down on its own in a zero gravity environment unless a force is applied on it.

In space where there is near zero gravity, you do not need much force to keep the inertia of motion continuing or even initializing it from a state of rest. In this kind of situation, even particles that are a result of electromagnetic emissions can serve as propellant fuel. This does not mean we are witnessing a reaction less motion if there is such thing; the voyage in a spacecraft carrying tangible payload is indeed governed by laws of classical mechanics which rules out any such notion. Particles emitted by the electromagnetic radiation such as light wave is creating the reaction which is propelling the spacecraft towards constant acceleration. This constant acceleration poses some issue which brings us to the world of quantum physics but I will leave that out from this post to keep it simple. Now combine that reaction with the sling shot maneuver (a technique to capitalize on the orbital motion) and you have tremendous speed at hand.

 

[Delta4Embassy]

I read that it could get us to Mars in weeks and potentially to the nearest star in 30 years. The key word there is POTENTIALLY! But man if this is the next revolution in space travel I hope I get to live to at least see the beginning of it.

Nearest star is Proixma Centauri at about 4.2 light-years. So ~30 years makes it's speed about 1/7th c or ~45,000KM/sec.

As with every other high-velocity method, shielding is going to be the biggest issue, not the drive, or even keeping the crew alive with adequate stores. What happens when you hit a grain of sand at 45,000 KM/sec? Nothing good.