Nasa worth it? (thread split)

[Kryssan]

The "fuel" used in fusion reactor is the most abundant element in the universe (hydrogen). While deuterium (instable hydrogen) isn't as common, it's still easy to find. In this case, it's the reactor itself that is the limiting factor. It would be similar to have a car engine breaks every 10 sec when the fuel tank is filled.

Edit: Noticed this - Deuterium is not unstable. Deuterium is stable. Tritium is unstable.

There isn't hundred of way to turn energy into electricity. Beside photovoltaics panel (solar panel) and electrochemical cells (batteries), the only method we have is to transform kinetic energy (heat, movement) into electricity using generators. Even in the case of nuclear energy, it always come down to boiling water to make a turbine spin. A glorified steam machine basically.

This isn't completely accurate. Several nuclear devices, what we like to call 'nuclear batteries' (though this term isn't accurate at all, it simplifies the explanation to others), have been designed and implemented. These devices use radioactive decay combined with the Seebeck effect and thermocouples to produce electrical power. They are properly referred to as RTGs (radioisotope thermoelectric generator).

New technologies are being implemented and tested with the RTG design, basically through use of thermophotovoltaic cells and sterling engines.

Point being, you don't need a turbine to make electricity with nuclear power. RTG, SRG, etc will never replace a nuclear power plant though; they have low efficiencies (anywhere from 3% to the low 20% range, depending on the technology used - with I believe SRG designs having the highest efficiency ratings) and you're certainly not getting KW or MW out of them (so for single use remote device applications they are spectacular, but you'll not be seeing RTG or SRG or etc powering your neighborhood).

Hm? I always thought that there's almost the same amount of anti-matter as matter, it's just that it couldn't be 'seen' with our current technology. Or did I read too much sci-fi and not enough textbooks?

I'm fairly certain this is not accurate. The universe started off with equivocal amounts of matter and antimatter in some simulations, but obviously is not composed of large quantities of antimatter anymore.

You're probably thinking of dark matter, which is pretty common. Antimatter is not as it annihilates matter when they come into contact.

Of course, dark matter being common doesn't do much for us because we're unable to interact with it at all.

Baryonic matter consists of about 5% of the universe (what most people are talking about, stuff on the periodic table, etc), with 20% being dark matter and the rest being dark energy. So far as we currently know / conceive of our universe currently. Of course, we really have little to no idea with dark matter or dark energy.

[Kaylia]

This isn't completely accurate. Several nuclear devices, what we like to call 'nuclear batteries' (though this term isn't accurate at all, it simplifies the explanation to others), have been designed and implemented. These devices use radioactive decay combined with the Seebeck effect and thermocouples to produce electrical power. They are properly referred to as RTGs (radioisotope thermoelectric generator).

New technologies are being implemented and tested with the RTG design, basically through use of thermophotovoltaic cells and sterling engines.

Point being, you don't need a turbine to make electricity with nuclear power. RTG, SRG, etc will never replace a nuclear power plant though; they have low efficiencies (anywhere from 3% to the low 20% range, depending on the technology used - with I believe SRG designs having the highest efficiency ratings) and you're certainly not getting KW or MW out of them (so for single use remote device applications they are spectacular, but you'll not be seeing RTG or SRG or etc powering your neighborhood).

Before the first edit, I was giving this and this as example, but I didn't want to clutter my post with additional technologies that are more or less exception rather than the rule.

Bane was talking about finding a simple technology that would solve every energetic problems, and while these nuclear devices have their uses, it's always going to be specific and limited.

I also didn't mean to imply that turning nuclear fusion into mechanical energy is the only way to go, but it does seem to be the only efficient way to handle a hydrogen fusion and recuperate the energy unleashed.



About deuterium, I guess I was wrong. I always thought it was much easier to fuse/fission than normal hydrogen.

[BaneTheBrawler]

Yeah, I didn't expect it to have any scientific viability. After all, if we can find a more efficient means of powering fusion than electricity, we wouldn't really need the fusion anyway because we could just use whatever we figured out.

It's just an interesting way of looking at the problem that I thought I'd share.

Edit: Also, for the anti-matter thing, the explanation I heard was that the pre-universe was perfectly balanced in matter and anti-matter, and then at the moment of the big bang, they annihilated each other... but 1% of the matter survived, and that's the stuff we can see. Not sure how Dark matter is involved in that. Maybe that's what you get when matter and antimatter interact. I dunno.

[Kaylia]

Hm? I always thought that there's almost the same amount of anti-matter as matter, it's just that it couldn't be 'seen' with our current technology. Or did I read too much sci-fi and not enough textbooks?

http://en.wikipedia.org/wiki/Baryogenesis
According to the Standard Model, the same amount of matter and anti-matter should have been created early in the Universe. However, whatever happened isn't what we think happened since there is clearly more normal matter. What does it mean? Nobody know. Maybe the anti-matter went somewhere else (a mirrored universe), maybe our theory is wrong, maybe the universe is simply so big that our sector isn't representative of what is everywhere else.

However, the theory itself isn't stupid. We can observe this symmetry pretty much everywhere (ie: inside the LHC, fusion reactor,etc), and it has been tested countless time.



http://upload.wikimedia.org/wikipedi..._Pie_Chart.png
Dark energy: It's the energy associated with empty space. It's where the virtual particles come from, and why forces are carried over a long distance by virtual particles. It's still highly theoretical, but one thing is certain, matter can be created out of "nothing".

Dark matter: It's matter that won't interact with electromagnetism (photons pass through it like it was nothing), but still has a mass. Again, nobody know what it is exactly, but at least, we can observe its effect indirectly because it will bend the space around itself like any massive objects.



Black hole, and anti-matter are also included with normal matter since that's what they are.

[Kaylia]

Edit: Also, for the anti-matter thing, the explanation I heard was that the pre-universe was perfectly balanced in matter and anti-matter, and then at the moment of the big bang, they annihilated each other... but 1% of the matter survived, and that's the stuff we can see. Not sure how Dark matter is involved in that. Maybe that's what you get when matter and antimatter interact. I dunno.

No popular theories allow us to make "pre-universe" claims (beside very special case of general relativity), what you probably mean is "right after the big bang".

Some theories proposed that the mutual destruction of particles/anti-particles isn't symmetric, but it's just a wild shot in the dark. Nobody really know, and nobody has observed anything like this. It's not impossible, but it's a guess that is as good as many others.

[Greatguardian]

That pie chart looks a lot more like what I was taught, as 1% of the universe feels like an extraordinarily small amount to produce the kinds of effects we attribute to dark matter.

For example, my brain fell asleep on me and I can't think of the term I want to think of. Crap. The thing with the observed gravitational field of galaxies and the constant rather than decreasing pull on peripheral stars. God dammit, I'll edit it in when it comes to me. Someone with more than a minor in astrophysics probably knows the phenomenon I'm talking about. Spiral galaxies shouldn't work the way they work without a lot of mass that "isn't there" in the rings.

Edit: Essentially, when dealing with large objects, we attribute the center of gravity to be a singularity at the center, yes? Looking at a spiral galaxy from the singularity going out to the rings, you start out with lots of mass right next to the singularity - meaning lots of gravity. As you move outwards, you get more mass, but at a lower rate (as the density decreases), and your distance from the singularity increases which means decreasing gravity. However, rather than decreasing gravitational effects, what's observed is a constant as you move further out. The only way to balance out the increasing distance from the singularity to theoretically maintain that observed constant is to add additional matter. So there has to be a lot more matter there that we're not observing, eg Dark matter.

[Kaylia]

What Bane meant is that whenever a "particle" meet it's "anti particles", certain theories proposed that there could be a low chance for the "particles" to survive (1%, 0.0001%, or 10%...it doesn't matter). It's essentially what I linked above:


Baryogenesis
In physical cosmology, baryogenesis is the generic term for hypothetical physical processes that produced an asymmetry between baryons and antibaryons in the very early universe, resulting in the substantial amounts of residual matter that make up the universe today.

Even if 1% survived, if the phenomenon happened multiple times in a row, the end result could explains the current 5% 20% 75% numbers.

For example, my brain fell asleep on me and I can't think of the term I want to think of. Crap. The thing with the observed gravitational field of galaxies and the constant rather than decreasing pull on peripheral stars. God dammit, I'll edit it in when it comes to me. Someone with more than a minor in astrophysics probably knows the phenomenon I'm talking about. Spiral galaxies shouldn't work the way they work without a lot of mass that "isn't there" in the rings.

Cosmological constant? Red shift? Expansion? Gravitational lensing?

The "arms" of a galaxy can't be explained if there was only matter, you need to add anti-matter to explain their behaviors.


[edit]
You're right about that. Dark matters has to be postulated to explains most movements on a galactic level (galaxy rotations, galaxy cluster). One of the most convincing (and visual) methods however is gravitational lensing since you can actually see the effect more or less directly.

[Greatguardian]

Oh, I know. I was talking about Dark matter, not anti-matter. And I just realized I completely misinterpreted Kryssan's post in the first place. I had misread "Baryonic matter consists of about 5% of the universe (what most people are talking about, stuff on the periodic table, etc), with 20% being dark matter and the rest being dark energy." as "20% of the 5% of the total universe is dark matter", and that sounded really off. My brain has completely shut down on me. Dark matter is not baryonic matter. derp.

[Greatguardian]

Bump for NDT stuff.

This is from the National Space Symposium last month.



Also, NDT addressing a congressional committee (or 3 members of one) about a month before that,



Thoughts?

In particular, the chicken and the egg. Does a culture of innovation fuel NASA, or does NASA fuel a culture of innovation? Are they co-dependent? Can one be revitalized without the other, and if not how can both be revitalized simultaneously?

[Stanislaw]

In particular, the chicken and the egg. Does a culture of innovation fuel NASA, or does NASA fuel a culture of innovation? Are they co-dependent? Can one be revitalized without the other, and if not how can both be revitalized simultaneously?

Well, if we look back in history and see what fueled the innovation of NASA, it certainly wasn't the 'culture of innovation', but rather it was because of the Cold War and two superpowers showing off who's got the bigger yard stick. For better or for worse, competition is the best motivator for technological advancements. Rivalry is good fuel, and war is simply that ultimate form.

If China manages to land someone on the moon in the next decade or so, I'd think we'll see NASA revitalized to its former glory. As horrible as China is as a country, it's one part I'm secretly rooting them on for.

[Mizango]

Oh hey, howd I miss this?

[Kryssan]

Oh hey, howd I miss this?

Oh, I'd say it is fairly elementary, my dear Watson.

I'm studying Cosmology..

Dat nigga wanna do hair...wtf....

Too much hair.

[Dimmauk]

Oh, I'd say it is fairly elementary, my dear Watson.





Too much hair.

LOL

[Rhinox]

Not gonna lie. When I first saw this topic the first thing I thought of was Miz Going Beastmode and morphing into NDT and laying the smackdown on anyone talking shit.

[Mizango]

Oh, I'd say it is fairly elementary, my dear Watson.


Too much hair.

haha, dayum.

Not gonna lie. When I first saw this topic the first thing I thought of was Miz Going Beastmode and morphing into NDT and laying the smackdown on anyone talking shit.

lol, which is why im pissed at myself

[Ryany]

Maybe it was posted earlier in the thread, but I noticed on the tax receipt thing from the White House that NASA is 0.6% of the federal budget according to their numbers.

If it really only is 0.6%, it seems to me it would be more worth it than just about anything. (and yeah I'm sure it was a lot bigger chunk of the budget when we got the most out of it)

[Cantih]

Not NASA, but the NSF
http://www.washingtonpost.com/blogs/...ddKU_blog.html

Bold mine.

On Thursday, on a mostly party-line vote, the House passed an amendment by Rep. Jeff Flake (R-Ariz.) to prohibit the National Science Foundation from funding political science research. And, in doing so, it politicized one of the main ways this country funds scientific research.
“My amendment does not reduce funding for the NSF,” he explained. Rather, “this amendment is simply oriented toward ensuring, at the least, that the NSF does not waste taxpayer dollars on a meritless program.” Well, what Flake considers a meritless program, anyway. As Christopher Zorn writes, the NSF runs a widely respected peer-review program that decides what science to fund. If Flake wanted to reduce the funding available to the NSF in total, that would be one thing (and, to be fair to Flake, he has proposed that in the past). But what he’s doing here is telling the NSF what is and isn’t acceptable science to fund. That’s not how scientific decisions are supposed to work. And the effect could be chilling.
Flake was quick to give examples of the “waste” that motivated his amendment. There was the “$700,000 to develop a new model for international climate change analysis” and the “$600,000 to try to figure out if policymakers actually do what citizens want them to do.” In other words, Flake didn’t like the kind of research that the NSF was funding in the political science arena, and so he barred the NSF from funding political science at all.
Now imagine you’re part of a discipline that isn’t political science, but that relies on NSF funding. Or imagine you’re on one of the NSF panels that funds those disciplines. Think you’ll be a bit more careful about submitting or greenlighting work on climate change? Of course you will.
If Flake had cut NSF funding, that would be one thing. Instead, he inserted politics — and his personal preferences — into the NSF’s funding-review process. That’s a much more dangerous precedent to set.
I have conflicted feelings about the public money that goes to academic research — including political science — in this country. I admire and rely on the work that comes out of these disciplines. But for all the public money that goes to support them, there’s a decided lack of public-spiritedness in how they act.
The research is often locked away in pricey journals. There’s a premium placed on unnecessary convoluted rhetoric that confuses and dissuades interested outsiders. There’s almost no effort put into connecting research with the public debate — and academics who try and engage in it often risk professional and social sanction. If it were up to me, any research that took even a dollar of taxpayer funds would have to be in an open-access journal and stored in a publicly searchable repository. While much of this research deserves public support, the prevailing mores in academia don’t.
But I have no conflicted feelings about wanting scientific decisions to remain free from meddling congressmen. Perhaps there’s some process by which the NSF could do a better job judging research proposals. But I’m quite sure that process doesn’t include Jeff Flake looking over the NSF’s shoulder, telling it which subjects he likes and which he doesn’t.

GOD DAMNIT ARIZONA, KEEP YOUR STUPID LOCAL, DON'T EXPORT THAT SHIT.

[Ragnus]

This shit had better get shit canned in the Senate.

[Mrbeansman]

This guy deserves props. It takes a special kind of douche to Scoff at global warming research and then go on and on about how where depriving our grandchildren of their future by borrowing money in one sitting.

[Stanislaw]

Bump. Some good (?) news on the space development frontier.

http://www.guardian.co.uk/science/20...gold-asteroids

Asteroid mining: US company looks to space for precious metal

Deep Space Industries hopes to land spacecraft on asteroids and have them scrape up material for return to Earth for sale

http://static.guim.co.uk/sys-images/...-outer-010.jpg
Deep Space Industries hopes to mine materials from asteroids hurtling past Earth. Photograph: Alamy Creativity/Alamy

A US company has unveiled plans to launch a fleet of spacecraft to hunt for small asteroids that pass close to Earth which might one day be mined for their precious resources.

Deep Space Industries aims to fly a series of low cost prospecting satellites in 2015 on missions of two to six months, with larger spacecraft embarking on round-trips to collect material a year later.

Announcing the proposals, chairman Rick Tumlinson said that resources locked-up in nearby asteroids were sufficient to "expand the civilisation of Earth out into the cosmos ad infinitum".

The first prospecting missions with what the company call FireFly and DragonFly probes could hitch a ride into space on the launches of large communications satellites, it said.

The company hopes ultimately to land spacecraft on hurtling asteroids and have them scrape up material for processing in space or for return to Earth for sale. One long-term idea is to build a space-borne manufacturing facility that takes in asteroid material, processes it into usable alloys and other substances, and makes objects with the material via a 3D printer.

The ambitious plans come less than a year after another US company, Planetary Resources, backed by Google's Larry Page and Eric Schmidt, and the film-maker, James Cameron, revealed independent plans to harvest valuable minerals and metals from passing asteroids.

Asteroids vary in their compositions, but some are rich in the platinum group materials and other highly valued metals. Some asteroids are largely made from nickel-iron alloys.

Mark Sonter, a consultant geologist with the Deep Space Industries, said about 1700 near-Earth asteroids are known that are easier to fly to than the moon. Almost all of the material found in asteroids has commercial value, from the silicate gravel to metal alloys and water, he added. "It's potentially extremely valuable material," he said.

At a presentation at the Santa Monica Museum of Flying in California, the company called for investors who might be interested in backing the company. "It's going to be an exciting ride," said Tumlinson.

Scientists and engineers who spoke to the Guardian said that mining asteroids was feasible but unlikely to make commercial sense for several decades, when the cost of launches came down, and prices of resources on Earth rose.

Keith Cowing, editor of NasaWatch.com, said he was not yet convinced by Deep Space Industries' plans. "Is the prospect of using asteroid resources crazy? No it's not. Is if difficult? Yes it is. Can you make a business case for it? People are trying, and making progress."

But he said any company must have a product, experienced people and a business case. "This is like a three-legged stool. You need all three legs, otherwise it's not a business, it's a hobby," he said.

Ian Crawford, a planetary scientist at Birkbeck, University of London, said some asteroids are made of highly valuable materials that are in growing demand by industry. "The time may come when the rising cost of these materials on Earth, due to dwindling availability and greater demand, makes the price of mining them from asteroids competitive. In principle, mining asteroidal material could become economical within a few decades," he said.

Building an industry that specialises in asteroid interception and mining might serve us well in the future, should a lump of space rock be spotted on a collision course with Earth. "The infrastructure that helps us mine asteroids could help us to divert any incoming asteroids too," Crawford said.

Fred Taylor, who is Halley professor of physics at Oxford University, said the launch of cheap and compact satellites to look for small asteroids close to Earth was conceivable by 2015, but much more needed to be done.

"Proper prospecting and eventually mining is much further off, difficult and expensive. Presumably they are after platinum and rare earths, and there may come a time when they are so valuable it makes sense to look for them in asteroids, but I can't imagine it will be commercially viable any time soon," he added.