Reactionless Thrusters for real???
 

http://www.independent.co.uk/life-st...-10215544.html

The name of the article is rather misleading. It seems to be talking about a kind of reactionless thruster that uses microwaves to generate thrust. Supposedly they say it could accelerate a ship up to 0.10c and reach Alpha Centauri in 96 years. I ran the numbers and that suggests an acceleration of about 0.002 G's. Dunno if it's real or not, but the possibilities are something to think about. It may not open up the stars for us, but it would make traveling around the solar system a lot easier.

Re: Reactionless Thrusters for real???
 

If this turns out to even be workable, it still isn't reactionless. The reaction mass merely exists at all points in the universe already, so you don't have to carry a fuel tank with you. Conveniently, the exhaust self-annihilates, too, so you aren't irradiating everything behind you, either. NASA is still poking this idea, but it has plenty of skeptics, too. It does make a cool basis for a constant acceleration drive, though! Easily as workable as any other scifi thruster for sure. And you get to use "force field", "quantum vacuum", and "virtual particles" properly in your technobabble explaination!

Re: Reactionless Thrusters for real???
 

emDrive has been around for a while, and it's hard to tell what specifically this article is talking about. In any case, the theory behind it is gibberish and the testing has been poor quality.

Re: Reactionless Thrusters for real???
 

And the inventor has made a number of wild claims, without allowing anyone else to examine his device. He also has a history of promulgating scams in the past. So it's hard to get enthusiastic about this.

And, frankly, it's a bald lie to claim that "NASA has verified his claims." What NASA said regarding the emDrive was an equivalent of "It's probably total bunk but, wow, if it did work wouldn't that be awesome?"

Re: Reactionless Thrusters for real???
 

It's constant-acceleration? How does that work out energy-wise?

Re: Reactionless Thrusters for real???
 

That is probably the more important stumbling block. A drive that uses no reaction mass is nice but fictional reactionless thrusters almost always ignore The Law of Conservation of Energy.

If this drive doesn't ignore the law the absolute limiting factor will be fuel for the power source instead of reaction mass.

Re: Reactionless Thrusters for real???
 

That article is quite vague, here's a much clearer article about the recent news. http://io9.com/new-test-suggests-nas...ork-1701188933

The above gives a good explanation of the experiment, and here's a skeptical article that doesn't focus on the experiment itself but has concerns about its reproducibility: http://www.popularmechanics.com/scie...e-controversy/

Assuming this isn't cold fusion and the effect turns out to reproducible, it seems pretty interesting. Far less impressive results than its big proponent predicted, but could still be useful.

Re: Reactionless Thrusters for real???
 

There have been no peer-reviewed papers about any of it (and NASA doesn't keep secrets about this kind of thing - they encourage their scientists to publish). nasaspaceflight.com (where most of this seems to be coming from) is not NASA nor even affiliated with NASA.

Until someone proves it via the usual scientific channels (peer-reviewed articles published in reputable journals and based on work by multiple un-related teams), it's just a rumor.

I want it to be true as much as anyone, but it's science fiction, not science, at this point.

Re: Reactionless Thrusters for real???
 

Okay, I read the other article and it puts the acceleration at 0.001 G's. Not a lot but still better than the Ion Drive in GURPS Spaceships, which I've heard are unrealistically powerful compared to reality.

Re: Reactionless Thrusters for real???
 

Cold fusion, but still fun for gaming appetites.