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The Amazing Properties of Aerogel
RideMax writes "We all know NASA is using a substance called 'aerogel' in the Stardust spacecraft to catch pieces of the Wild-2 comet. The NYT is running an article about some other amazing aerogel properties. My favorite quote: 'It's the lowest density of any solid, and it has the highest thermoinsulation properties. Though it would be very expensive, you could take a two- or three-bedroom house, insulate it with aerogel, and you could heat the house with a candle. But eventually the house would become too hot.'" We've looked at Aerogel before.
If you goddamn kids would close the goddamn door!
I have been pwned because my
aka Vaporware... Made of 99.6 percent empty space, the little cube is indeed barely there, with a density one-hundredth that of the hand that holds it.
- It is 99.8% Air
- Provides 39 times more insulating than the best fiberglass insulation
- Is 1,000 times less dense than glass
- Was used on the Mars Pathfinder rover
And a cool picture of aerogel in somebody's hand.--
For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.
What if it was only used to certain walls where leakage was most common?
Or perhaps to insulate between windowpanes? Since it's more or less transparent, it'll let the light in, but not heat out...
Everything in the world is controlled by a small, evil group to which, unfortunately, no one you know belongs.
It also has incredible compressive strength. "It can take 2,000 times its body weight without damage," Dr. Tsou said. NASA's Web site shows a 2-gram cube of aerogel (less than 0.1 ounce) supporting a 2.5-kilogram brick (about 5.5 pounds).
That particular example doesn't seem that impressive, I used to build balsa wood structures that would hold over 600 lbs(~270kg), with only 15 grams of balsa wood and glue, with strict rules on how it could be built. The world record is somewhere in the 1500 lb mark with a similar weight of wood.
Very good Aerogel FAQ.
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For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.
Not sure if all Aerogels are created equally, but this is from 1999 NASA article on Aerogel:
"A single one-inch thick windowpane of silica aerogel is equivalent to the insulation provided by 20 windowpanes of glass (R-20 insulation factor)."
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For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.
let me get this straight....virtually unbelieveable insulation at the coldest of temperatures...creating super greenhouses/habitats and so forth...
improves the desalination of seawater plants a thousand fold...
my god....all we have to do is find a cheap or easier way to produce (like we do with virtually everything in the world in the free enterprise system) and we can offer virtually energy free habitats (excess heat can be channelled into electronics and solar can pick up the rest) - as well as a cheap water supply for the world...
christ...someone get me some chemists and a few venture capitalists.....this is incredible... - and it's real and now...not like those carbon nanofibers people want to use to create space elevators...
pax
RB
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ah honey, we're all resplendent - Bill Mallonee
The article doesn't touch on it, but the NASA FAQ mentions this unique property...
Q: What happens if I touch it?
A: Silica aerogel is semi-elastic because it returns to its original form if slightly deformed. If further deformed, a dimple will be created. However, if the elastic limit is exceeded, it will shatter catastrophically, like glass.
Some cool shots.
Here's a nerdy factiod about aerogel that might help your processor speed.
There has been some close research into using substances like aerogel to improve processor speeds. Apparently the substances can be used as very efficient insulators between traces and components. This is because aerogel and substances like it are mostly made of air, which has a very high dielectric constant so aerogel itself is a very good insulator.
It's better described here
This informative comment was lifted from a comment made the last time aerogels were discussed on slashdot (see the original comment here).
While I'm sure aerogel has many pracitcal uses (trying not to fall asleep here), the "cool" factor is also very high. I've seen some of her samples, and everything the article says is correct. It's so light it feels like the wind could take it; in fact, if you drop it in water, I think it dissolves. Since the material is so expensive, it's obviously something you don't want to do, since every last piece is precious.
As you might imagine, a material that's ultra-light and 'holographic' has artistic applications, too. The "brain" image made it onto the cover of Nature neuroscience, and wouldn't look out of place in a design magazine. When you see it up close, the image seems to be 'embedded' in the material, even though it's so light you could easily crush it with your hand. The airiness and delicacy of the material makes the image that much more striking.While we're all attuned to the utilitarian value of materials like this, it's always neat to see what people outside of engineering can do with them.
Check it out - this auction on Ebay is selling a 4-6 Cubic inch chunk of Aerogel with a "Buy it Now" price of $160. Considering the auction says it costs about $200 per cubic inch to make, thats a deal. I'm guessing some /.'er with deep pockets will be buying this pretty soon!
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For those of you who like stupid science tricks/supercheap climate control, here's a trick for how to heat and cool a house without using any energy (outside of what's free from the Sun):
/ blackbody/bbody.html), which gives 300-500W/m^2 at typical Earth temperatures (over 400W/m^2 heat loss at typical room temperature).
First, some background on black body radiation. All matter radiates some light, based on its temperature. By basic thermodynamics, the amount of radiation that a color of matter absorbs in a given frequency range (as opposed to reflects) is directly proportional to how much it radiates (as compared to a perfect black body of the same temperature).
The sun only radiates on a fairly small set of frequencies, and that set is very different from the frequencies at which a black body at room temperature radiates. If you build a panel of a material that is perfectly absorbent in the frequencies on which the Sun radiates (perfect black body), but reflects in the remaining frequencies (perfectly white on the blackbody frequencies of room temperature), it will lose very little heat to radiation, but absorb a lot from the sun, and it'll get very hot. If you take a body that reflects radiation in the colors the sun emits (white), but absorbs/radiates elsewhere (black), it'll get very, very cool, even in bright sunlight. You can get pretty close to the full 1000W/m^2 of heating (level of Sun's radiation hitting the earth). In cooling, you get pretty close to the ideal from Stefan's Law (http://www.egglescliffe.org.uk/physics/astronomy
This means that you can theoretically heat or cool a house with just a painted square on the roof a few square meters in area, if you could just create a material of the right color.
Problem is the guy who came up with this (and showed it to me) was a physicist and not a chemist, and had no idea how one would go about creating a material whose color was that well controlled.
Still a nifty concept, eh? If you could make this, it would save a ton of energy, since you'd no longer need to burn gas to heat and use electricity to cool -- just flip a panel on your roof, and the temperature changes (although for heating, the house would need to be well enough insulated to last the night).
Ref: The Third Industrial Revolution by G. Harry Stine.
See CDT Water for one practical, functional application of aerogel.
In short, they push contaminated water through aerogel and use electrodes to pull ionic molecules apart. The ions get caught in the aerogel mesh, and the purified water flows through. At least, that's my layman's understanding of it.
Cheers
-b
If I wanted a sig I would have filled in that stupid box.
Maybe I'm missing something, but elsewhere they said "But, Dr. Tsou said, the material was not used much, except in powdered form as a nontoxic anti-caking agent for food."
If it's so expensive, what kind of food exactly were they using it on? Caviar?
This Space Intentionally Left Blank
If Aerogel is that good at insulation, screw the candel, i'll just rely on the body heat of myself and others :/
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The pictures are amazing. Wow. http://stardust.jpl.nasa.gov/photo/aerogel.html
"You could take a two or three bedroom house, insulate it with aerogel, and you could heat the house with a candle."
Well, sure, anybody can point out the obvious "if you have a crack in your house" stuff, but the idea is still valid. So, don't go pulling out pivnert from 10th grade chemistry and using that as your basis for second-guessing an illustrative statement.
However, your house would STILL get too hot, even using PV = nRT. V here is constant. R, of course, is the Rieberg constant, the value of which I don't know off-hand. As long as no air leaks out, then as T goes up, P goes up accordingly. But T is on an absolute scale. Kelvins, here. 293.15 K is room temperature, 20 degrees C, and if you heat that up to 30 degrees C, 303.15 K is, in terms of proportionality, not too much of an increase, but hotter than is comfortable, i.e. too hot. Then particles, due to the pressure differential between outside and inside, want to leak out that crack. And what's happened? THE TEMPERATURE HASN'T DECREASED. n in PV = nRT has gone down in order to bring P down to atmospheric pressure outside. Oh, dear, T is higher, and nothing's leaking out! This, silly head, is why it's possible to heat a house in the first place. By your reasoning, a house could never be a different temperature than outside! Which, thank goodness, isn't the case.
And then, of course, "as a matter of fact," the air is exactly what keeps it hot, and any other thermally insulative materials, i.e. fiberglass or aerogel. When you heat up a house, you run air into a furnace, heat it up, and then pump it through the rest of the house. A candle would heat up the air immediately above it (rising products from chemical reaction) and that air diffuses throughout the house, heating it up. Just like your furnace. True, there's radiative heating from the candle as well, but compare the difference in heat when you stick your finger an inch above a candle vs. an inch to the side of it. Radiative heating is universally dispersive. Convective goes straight up. BIG difference between the two there. Oh, well, it looks like a candle COULD heat up the house insulated with aerogel.
Yes, I am a physicist.
From What's an aerogel?:
Vacuum is *not* actually the perfect insulator. It is true that no heat is conducted trough vacuum, but on the other hand vacuum is near perfect in letting heat *radiate*. Now, if you combine vacuum with one or more reflective films to reflect back most of the radiated heat then you have eh, uhm, invented the termos-bottle.
Powder is cheap, but the bulk aerogel made from it is a little bit of a trick.
Iron is pretty cheap too, but a single perfect crystal of appreciable size starts to make Platinum look positively affordable. Or graphite to diamond.
It's not so much the atoms that make many things expensive so much as how they're put together.
Insulation isnt really the problem anyway. It's easy to make a house you could heat with a candle. Modern houses in countries with cold winters have triple glazing and good insulation, with negligable heat loss through windows and walls.
The problem is ventilation. Even apart from the issue that you'd suffocate, houses that are too insulated are almost guaranteed get mold problems. You need a constant airflow, and that's where you get the major heat loss. Of course, various techniques like heat exchangers exist to ameliorate this, but unfortunately the technology for 100% efficiency is not quite there yet.
Diamond is usually made from carbon, same stuff graphite is made from, but in a different configuration. So, in theory, if you rub it against paper, it should leave a mark.
I should have known this before I proposed to my girlfriend.
I could care less, but not without a lobotomy
"Aerogel": A Ridiculous Liberal Myth
It amazes me that so many allegedly "educated" people have fallen so quickly and so hard for a fraudulent fabrication of such laughable proportions. The very idea that a solid material happens to be so light, showing remarkable properties like near-perfect insulation, is ludicrous. Furthermore, it is an insult to common sense and a damnable affront to intellectual honesty and integrity. That people actually believe it is evidence that the liberals have wrested the last vestiges of control of our public school system from decent, God-fearing Americans.
I could care less, but not without a lobotomy
The short answer is that yes it could, but only temporarily.
I believe Aerogel is an open celled matrix, meaning that the eventually the hydrogen (especially hydrogen) would leak out causing a block of the stuff to return to the ground.
I suppose it would be possible to seal a block of aerogel in some sort of polymer making for a structurally solid balloon.
..of ships and shoes and sealing wax, of cabbages and kings.
On a more serious note, I wonder if this stuff has any radiation shielding properties? When they fired particles into the gel, they were very quickly stopped. And placing the gel against a bunsen burner doesn't even phase it. If it protects against radiation just as well, its light weight may make it the perfect space ship shielding material.
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