Community > Forum > National Aeronautics and Space Administration (NASA) > Dr. Griffin about private space vehicle companies...

Dr. Griffin about private space vehicle companies...

Posted by: Ekkehard Augustin - Fri Aug 18, 2006 1:10 pm
Post new topic Reply to topic
 [ 22 posts ] 
Dr. Griffin about private space vehicle companies... 
Author Message
Space Station Member
Space Station Member
User avatar
Joined: Mon Aug 16, 2004 7:09 pm
Posts: 485
Location: Maastricht, The Netherlands
Post    Posted on: Tue Oct 02, 2007 6:07 am
campbelp2002 wrote:
Stefan Sigwarth wrote:
What i understand that the He3 reaction doesn't produce certain particles that damage your reactorwall. With every other reaction it does and you would have to rebuild the reactorwall completely.
Then you heard wrong. The Boron-11 reaction does not do that either. Boron-11 is just as good as Helium-3 and is in plentiful supply on Earth.
Let me say that again. Boron-11


I may have read it wrong, but i'm not a moron. So try to say it normally next time okay?


Back to top
Profile
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Tue Oct 02, 2007 1:07 pm
Stefan Sigwarth wrote:
I may have read it wrong, but i'm not a moron. So try to say it normally next time okay?
Sorry.


Back to top
Profile WWW
Space Walker
Space Walker
User avatar
Joined: Wed Jul 28, 2004 8:30 am
Posts: 236
Location: Perth, Western Australia
Post    Posted on: Thu Oct 04, 2007 5:59 am
Yep I can admit to be a 'BORON' since I automatically assumed that when people were talking about fusion reactors they were referring to Helium processes. :oops: U know how it goes, assume makes an 'ass' out of 'u' and 'me'

Now I know better and in relation to research can contribute (although I'm sure the more scientifically oriented here are already well aware of this) the following site on the ITER project which isn't concerned with Helium of any sort at all but is concerned with producing a workable fusion reactor.

http://www.iter.org

So there goes my theory on the Moon and helium 2 or 3 or whatever.

_________________
Beancounter from Downunder


Back to top
Profile
Moon Mission Member
Moon Mission Member
User avatar
Joined: Tue Oct 05, 2004 5:38 pm
Posts: 1361
Location: Austin, Texas
Post    Posted on: Thu Oct 04, 2007 1:14 pm
The guest on a recent space show very succinctly stated why there is no reason to go to the Moon for helium-3.
1) We have helium-3 on Earth. Not much, but enough to do research with.
2) We don't know how to fuse helium-3 and no research is being done to learn how.

I'm sorry to have blasted Stefan that way, but glad that it had the intended result of getting boron-11 on the radar of people who probably never even considered it before.


Back to top
Profile WWW
Space Station Member
Space Station Member
User avatar
Joined: Mon Aug 16, 2004 7:09 pm
Posts: 485
Location: Maastricht, The Netherlands
Post    Posted on: Thu Oct 04, 2007 1:29 pm
campbelp2002 wrote:
, but glad that it had the intended result of getting boron-11 on the radar of people who probably never even considered it before.


That sure did it :)

But research is done at a such a slow pace, i remember hearing of ITER in 96 or 97 in my physics class on high school. And they haven't produces a single net watt out of it. Yet. So before it even can become commercial, ITER has some more decades to go. So i don't see fusion as a viable option, simply because it will come 'too late'.

For now, it's perhaps wiser to stick what we got and do the research and science on Earth, and to start building a future on the moon & Mars. The moon could be used as a testbed for constructiontechniques in low gravity. But that isn't NASA's job, i'm not really sure if it was absolute the momen Neil Armstrong stepped onto the surface. That was the only goal for NASA and why it was installed/created.

Anyway, the cost of going to space isn't gonna drop significantly because of the rapidly rising energyprices. Unless we have something going before the prices are too high, it's only gonna happen when we have a new supercheap energysource.


Back to top
Profile
Spaceflight Enthusiast
Spaceflight Enthusiast
avatar
Joined: Thu Aug 06, 2009 10:18 pm
Posts: 1
Post Re: Dr. Griffin about private space vehicle companies...   Posted on: Thu Aug 06, 2009 11:38 pm
FWIW, I readily agree that ITER is a beast of unbelievable proportions. In a lot of ways, it is the ultimate expression of how risk aversion actually wastes resources, because the Tokamak was effectively a dead end when it was at Princeton over a decade ago. This approach will simply never be of commercial use, and in fact its research value is highly dubious as well... though it certainly keeps a load of researchers on a payroll.

In any case, this position is also what Bussard believed, and as he was the driving force behind the EM "pinch" approach that is still going strong, I guess one has to concede that Boron 11 has its place, and has potential. However, because of its nature, it may also be impractical as a viable power generation alternative.

The reason He3 is sunch an interesting angle, is simply that it really has the potential to be the real deal, a true "game changer". The fact that He3 is so stable, and so small, is both a challenge and a boon. Getting practical power from a thermal reaction is almost certainly out of the question. As someone pointed out, the coulomb barrier (the electrostatic repulsive force of the nucleus) is so high (around 1MeV) in a He3 - He3 reaction, that it is almost impossible to imagine ever getting enogh collisions in a plasma to generate positive energy. Even with a mix of Deuterium and He3, (technically also aneutronic), there would be so many side reactions between deuterium atoms (which definitely does produce neutrons aplenty) that the overall process would not be aneutronic.

However, magnetic containment is not the only way to get nuclei to fuse, and there may be the possibility for breakthrough technologies that make use of this. For example, it has been suggested, that with a geometric arrangement of double walled carbon nanotubes, each creating an electric field which would tend to create a stream of He3 ions in a single line with extrardinary precision (kepping them central to within several proton diamerters), a stream of ions could be directed towards an opposing stream wherein an extremely high fraction of them would pass within the range of the strong nuclear force, securing fussion.

Such an approach would use an array of these tubes, aligned and being perfectly straight geometrically, angled at the center. Nuclei that fused when have all of the energy in their speed, which could be readily captured directly as electricity through electrostatic containment within the reaction chamber.

Keep in mind, that this approach is one of several that could yield such a breakthrough. In the interest of sobriety, also keep in mind that a helium 3 nuclei even in the smallest possible nanotube (12 Carbon rings in circumference) it is more or less like a stream of peas in a tunnel opening several hundred yards wide. Engineering it would be difficult. But it does not seem impossible.

The final point here is that had breakthrough technologies been the focus of our civilization during the last few decades, rather than the debacle of things like ITER (which ironically, was done under the idea of an incremental approach), we would have a decent likelihood by now of having something viable, if not solved, in our hands right now.

With a solution, we could indeed be looking at the moon as the source for cheap clean energy that would support humanity with low cost and wasteless energy for several centuries at least. Several places oin the moon with high concentration of titanium in the regolith, are likely to have quite high concentrations of He3, and with cheap energy, commercial exploitation and infact colonization of the moon would be at hand.

I would also add finally, that without a breakthrough like this in fairly short order, there is an extremely high risk of forces being unbound in the coming years that will potentially result in the wholesale re-ordering of our societies, and undoubtedly to all of our great detriment, and to that of posterity. Sustainability is not visible in any meaningful way through any of the much lauded solutions that use "sustainability" as a buzzword.

We need this, and we need it quickly, or I really fear our children will inherit a world in steep decline, and a civilization with its apex rapidly becoming merely a bitter memory.


Back to top
Profile
Space Station Commander
Space Station Commander
User avatar
Joined: Mon Oct 06, 2003 9:22 pm
Posts: 843
Location: New York, NY
Post Re: Dr. Griffin about private space vehicle companies...   Posted on: Tue Aug 11, 2009 1:43 am
wow that's a great post.

thanks for the insight, i have never heard about this possible technology for fusion.

_________________
Cornell 2010- Applied and Engineering Physics

Software Developer

Also, check out my fractals


Back to top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 22 posts ] 
 

Who is online 

Users browsing this forum: No registered users and 10 guests


© 2014 The International Space Fellowship, developed by Gabitasoft Interactive. All Rights Reserved.  Privacy Policy | Terms of Use