Why does NASA use gold foil on equipment and gold-coated visors?
physics.stackexchange.com
physics.stackexchange.com
Can you give some more details about this?
† http://news.google.com/newspapers?nid=1499&dat=19560213&id=4...
‡ http://rstl.royalsocietypublishing.org/content/65/484.full.p...
[1] http://articles.adsabs.harvard.edu/full/1973NASSP3006.....P
[2] https://secure.flickr.com/photos/40605738@N03/3737695623/in/...
[3] https://secure.flickr.com/photos/40605738@N03/3737695681/in/...
[4] http://articles.adsabs.harvard.edu//full/1973NASSP3006.....P...
It has so many practical useful purposes besides rotting in a bank vault. But a lot of that potential is wasted on those that value it so highly for its scarcity rather than its utility. Why can't we just hoard iron oxide?
People are idiots and have let TV windbags convince them that a gold based currency is more "real". Shiny!
It's simply not "right" to tie the value of everything in society to the value of a specific good. Gold, like all other goods should be free to have a value that is intrinsic to its uses (of which there are many in science and engineering) and other goods should not be subject to price fluctuations due to supply and demand issues related to gold.
Obviously, people have issues with their fiat currency issuer – especially since currencies tend to be a government monopoly and lots of governments abuse that monopoly. However, that's well outside the point I was making. In any case, that's not an issue with fiat currency per se but with government monopolies on fiat currency (something that currencies like Bitcoin have set out to address).
Until someone discovers a mine that doubles reserves over night. Gold can be just as bad as paper with modern mining technology.
Zimbabwe kicked their inflation problem by dollarizing. Note they have plenty of gold to mine in that area.
The US dollar is still a very stable currency, whatever the libertarian alarmists claim.
2. User B lists a number of additional areas in science and technology that rely on the intrinsic properties of gold and bemoans financial system reliance on gold. Somewhat off topic and interesting discussion of fiat currencies ensues.
3. User C comments that gold is intrinsically worthless.
Great example of why I find HN so interesting and infuriating.
This is true for all materials and services.
> Gold as a concurrency is completely detached from gold as a useful commodity.
Is that your way of saying "I should not have said gold was intrinsically worthless"?
The way that fiat currencies have pretty much displaced commodity currencies suggest that this is actually a fairly widespread realization.
Hypothesis: Gold economies are more stable than fiat currency economies.
Expected observation: Gold economies have fewer economic crises and panics than fiat currency economies.
Actual observation: They don't.
Any recession is caused by "expanding production", the whole point of a recession is that it's a correction that happens after a boom cycle.
The list provided only shows that they also have crises -- it doesn't show how those crises measure (respective to fiat currency economies) in magnitude, frequency and consequences.
BTW, if fiat money are so great and gold money is so inferior, why exactly the government snatched the private gold in the 30s[1]? Did they want the inferior thing so much that they had to force people to give it up because they wouldn't voluntarily exchange it for the much better thing? I imaging they were rescuing those people, that's what it was. A sacrificial act by the Feds.
Your other argument is incoherent--there's no fundamental reason to build monetary policy such that it favors individual investors over the health of the economy as a whole. In fact, if people simply hoard money rather than spending and investing it, that's generally an indicator of a poor economic system that can cause the type of deflationary spirals that caused the Great Depression in the first place.
Here's an absolutely classic piece from the austrian view point. Take a read, it might expand your narrow views even if you don't agree!
http://www.amazon.com/The-Monetary-West-Jacques-Rueff/dp/B00...
I would have to guess that perhaps at most, 1 gram of gold would be needed for a space visor? The process involved in deposition must be considerably more expensive than the actual material involved (a gram of gold is about $44 at today's prices).
(Actually about 300 square feet can be covered by 1 ounce of gold (31.1 grams per troy ounce) I believe; so the amount would be less than 1 gram, but maybe they would waste some, etc. )
? This is supply and demand: the use as a currency/store-of-value is extra demand, hence the price is higher, and other users (like science) will demand less gold.
> The process involved in deposition must be considerably more expensive than the actual material involved (a gram of gold is about $44 at today's prices).
Which is ~$44 you wouldn't have to pay for another metal, and the penalties only get worse from there. (Want to manufacture a billion smartphones for Africa using efficient gold circuits? Sorry, not going to work out well.)
How much of that gold would we ever see again? (How much of the gold we use in electronics in wealthy nations do we ever see again?)
Quite a bit, I'd imagine: retrieving the gold is one of the reasons that electronics recycling exists.
You wouldn't have to pay $44 for another metal because they are vastly more abundant[1], the consequence of which is that they are cheaper to produce.
Yes, demand affects the price too, but given gold currently costs over $32/gram to produce[2] (average, individual mines vary considerably), I don't see how the price is going to magically drop if it stops being used as a store of value.
[1] http://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth'...
Gold is expensive because billions of people think it is worth hoarding. You don't have that percepetion with aluminum, so in a lot of circumstances where gold would act as a better substitute, you have to use the less efficient element regardless of physical scarcity because billions of people want to just stick that gold in a box and hoard it rather than use it, and that demand means an elevated price.
Gold isn't scarce because there isn't much on Earth in this sense. Gold is scarce because all the people hoarding it take that gold out of the market and there are billions of people that want gold not for practical utility of the element but to hoard.
Also, how much could NASA really be spending on gold, anyway? They're already spending billions on the rest of their space program.
You either have gold or you don't. Alchemy tried to convert elements into other elements which is nearly impossible (The sun and other nuclear reactions do this, but not directly to specific elements).
Somewhat interestingly, gold is actually being actively destroyed in particle accelerators, as it has several properties that makes it a desirable target. As my professor once put it, we finally have the secrets the alchemists only dreamed of, and we use them to destroy gold.
Which properties in particular make it a good target?
Edit: more details from wikipedia[2] suggest starting from either mercury or platinum, although it's all a bit fiddly and isotope-specific. That page has some other interesting facts as well - I'd never really thought of element synthesis as economically practical (and with capital equipment costs, probably still isn't), but tungsten ($30/kg) -> rhenium ($6k/kg) -> osmium ($12k/kg) sounds like a nice business to be in if you can solve the practical problems.
When the balloons all run out, we might want to start making our own helium as well, which has the bonus of being really quite easy to do.
[1] http://chemistry.about.com/cs/generalchemistry/a/aa050601a.h...
[2] https://en.wikipedia.org/wiki/Synthesis_of_precious_metals#G...
To convert other forms of carbon into diamond, you just need to simulate the conditions in which diamonds are formed (heat and pressure inside the earth.)
To convert other elements to gold, you just have to simulate the conditions in which gold is formed, which, as a heavy element, I'm pretty sure is reproducing a nuclear process that occurs in large stars or possibly supernovae, i.e., something you can reproduce only on Earth only on a very small scale using particle accelerators (or maybe nuclear weapons.)
Fusion only releases energy up to iron. Creating heavier elements consume energy in the reaction rather than releasing it, therefore cannot sustain a reaction.
https://en.wikipedia.org/wiki/Synthesis_of_precious_metals#G...
I think the inside of a star is not perfectly clear-cut. Various elements get created and cycle, with only the energetically-favorable ones accumulating. It's not altogether unlike chemistry.
What little I know of this comes from wikipedia, but I think there are other ways to synthesize elements apart from fission and fusion. Sometimes they simply catch a neutron, and the decay of a particle produces a different element.
Diamonds are a form of carbon, all you need is a different form of carbon and sufficient pressure. Gold is an element, and creating it requires a supernova. Were this not so, if gold could be synthesized, it wouldn't be selling for $1300/ounce.
That's not by itself true. If gold could be synthesized for less than $1300/ounce, then it wouldn't be selling for $1300/ounce. As noted in sibling comments, it is possible to synthesize. It's just unreasonable to actually do so in any meaningful quantity.
I thought this turn of phrase was rather amusing, considering that gold is often favored because it doesn't deteriorate at all.
During the Manhattan project they needed to build something with a ridiculous amount of copper coils, and copper was scarce due to the war. So they used silver instead. Who cares if it's more expensive, if that machine is going to be more heavily guarded than any bank anyway and you can always melt it back into ingots when you're done?
http://articles.latimes.com/1985-08-05/news/mn-3468_1_manhat...
†http://sensorsblog.com/uncategorized/counterfeit-gold-detect...
If I remember the story correctly, it was the door stop to a room that held fissible material - gold wasn't expensive compared to the materials they were working with!
Because it isn't scarce.
A more elaborate answer:
http://www.npr.org/blogs/money/2011/02/15/131430755/a-chemis...
I really gotta stop playing so much Kerbal Space Program.
But there are applications where gold is indeed used - but it's unclear (in the literature I've read) when/where it's appropriate to use gold. The helmet use case I can believe. I also imagine large swathes of gold would be problematic - structural surfaces being unnecessarily conductive or introducing inductive noise.
Source: http://www.nasa.gov/pdf/188963main_Extravehicular_Mobility_U...
http://en.wikipedia.org/wiki/Multi-layer_insulation
Of course, gold foil per se would end up being too heavy for a spacecraft thermal blanket.
I've used it to insulate south-facing windows in summer. It's phenomenally effective.
I once in a first aid training asked one fireman that was present to borrow me his helmet, because I was doubting you could see through it (I was 12).
The nice man put the helmet correctly on my head, and to my surprise, I really could see! Everything was blue, but I could see everything, it was really cool.
This article explained to me WHY I could see... I was still puzzled (I thought gold reflected 100% of visible light)
It depends on how thin it is. There is no 100%, the thinner the more is transmitted (weighted by the curve shown in the linked article). A solid block of steel would be transparent if you illuminated it with enough light.
On another tangent (this one's pretty cool) - since you can tune the properties of these nanoparticles, you can make them respond in a specific way. Let's say we have a cancer cell that we want to kill, and only that cancer cell should die. We can create nanoparticles that bond with that cancer cell, and only that cancer cell. But how do we kill it? We can tune the absorption spectrum of the nanoparticle to absorb infrared light - light that is transparent to the human body. We create a small heater that absorbs tons of the input energy, while keeping the rest of the area cool. Localized heating destroys the nearby cancer cell.
Plasmonics are really cool - http://en.wikipedia.org/wiki/Plasmon
The gold-leaf shielding in Sunshine was influenced by NASA satellite designs for deflecting heat and other forms of radiant energy. Boyle designed the gold-coloured space suits along these lines despite persistent encouragement to model them after the NASA template.
Time to take a break from HN, I guess.
†http://en.wikipedia.org/wiki/USS_City_of_Corpus_Christi_(SSN...