World's Lightest Solid

Erazmus writes: "NASA's Jet Propulsion Laboratory has manufactured the world's lightest solid. At only 3 milligrams per cubic centimeter, it's close to the density of air (1.2 milligrams per cubic centimeter). Spaceflight Now has the article. The article points to JPL's site, along with some amazing pictures."

Comments

good recipe:

[b_pretender]

quote: "It's probably not possible to make aerogel any lighter than this because then it wouldn't gel""

That's just a challenge to the Materials Science Engineers. Maybe that can make He-gel or H2-gel and get the *solid* material to be lighter than air... at least until gas-diffusion takes over and replaces all of the H2/He with O2. A thin membrane around the outside might even prevent this from happening! I can't wait for (air)floating surfboards and cloud-cities.

take a look at the aerogel photogallery.

Re:good recipe:

[MindStalker]

Yes, but if the total weight of you plus what your contained in is less than the weight of air, simple priciples of boyancy state that you will float up in air. If your weight is controllable (through a system of inflatable bellows for instance, like a submarine does) you can control your altitute and everything. Kinda like a blimb, only without the huge airbag.

Re:good recipe:

[Bullschmidt]

But you forget bouyancy. Just like things that are less dense than water float at the surface, things with a lower density than air (lighter-than-air) would float a certain distance up. This is just like helium ballons. A helium ballon is lighter than air. It wouldn't float in a vacuum, but it does in our atmosphere, at least until the density of the baloon equalizes with the density of air. Now, to have an air-surfboard, the stuff would have to be either pretty darn bouyant, or pretty big.

Re:good recipe:

[Captain Nitpick]

Now, to have an air-surfboard, the stuff would have to be either pretty darn bouyant, or pretty big.

Actually, it's just going to have to be pretty big. I can't find the density of the human body at the moment, but it's reasonably close to that of water, so let's use that number, 1000 kg/m^3 (this also happens to be a nice round number, easy to work with). Air at sea level has a density of roughly 1.2 kg/m^3. In order to float, you need to get the average density of person+board down to that of air (actually you need to be below it, but neutral bouyancy is interesting enough).

So, assuming a 100kg person, for ease of math, and assuming a massless board with a density of zero, the board would have to have a volume of over 83 cubic meters. (assuming I did my math correctly) For the metric-declined, this works out to a cube about 14 feet on a side.

Insulation

[DeadSea]

This stuff was used on Mars missions to capture particles so I thought it would be really expensive stuff. No way that you would ever be able to afford enough of it to actually insulate your house, even though it is 39 times better at it than the best fiberglass insulation.

Upon seaching Google for the cost of this stuff I ran across Aerogel Super-Insulation made by Aspen Aerogels. They don't have prices on their sites but it looks like somebody is trying to make an insulation product out of it. It says they are trying to break into the 20 billion dollar insulation market and that mass adoption of the product would greatly reduce fossil fuel use around the world.

Re:Insulation

[spike hay]

Actually, one of the things they are working on with this aerogel is to make it more transparent for window use. 20 times less thermal conductivity! Also, now they are selling warm aerogel jackets for large sums of money. Now, we always here about firemen getting killed in fires. Why don't we equip firemen with aerogel suits. Aerogel would keep them insulated better than Nomex. Also aerogel resists heat better than Nomex. If my memory serves me right, nomex (special plastic) can withstand 800 degrees. I believe aerogel can withstand about 2,000.

The big question:

[Goronguer]

Where can I get my hands on some of this stuff?

Seriously, how expensive is it to manufacture this stuff? If it were relatively inexpensive (or if it would be if produced in sufficiently large quantities) I could think of thousands of uses for it. Or rather, I could do thousands of useless things with it. At the very least, it would be neat to build a PC case out of it.

Anybody know?

Re:The big question:

[bgins]

A quick look suggests it might be a bitch to clean (the surface chemistry page says it is hygroscopic); and although it appears to be strong (as in the picture of it supporting a brick), it is also a bit fragile (which also looks like a good tip in case you do actually get your hands on some).

I wasn't able to figure out whether it would build up static electricity, and, not being an engineer or even knowing/remembering what Young's modulus, among other things in the physical specs is, I am of course only guessing, but I think it might be a better sound insulator (like a lining inside the case) than structural load-bearer (like a PC case).

If you want to waste some time on it, why don't you read through the info and brainstorm some more uses for it? I'd love to hear what you come up with. Interesting stuff.

Re:The big question:

[kaszeta]

Where can I get my hands on some of this stuff?

Here, for one place.

Re:Old news ....

[b_pretender]

"Aerogels had been largely forgotten when, in the late 1970s, the French government approached Stanislaus Teichner at Universite Claud Bernard, Lyon seeking a method for storing oxygen and rocket fuels in porous materials. There is a legend passed on between researchers in the aerogel community concerning what happened next. Teichner assigned one of his graduate students the task of preparing and studying aerogels for this application. However, using Kistler's method, which included two time-consuming and laborious solvent exchange steps, their first aerogel took weeks to prepare. Teichner then informed his student that a large number of aerogel samples would be needed for him to complete his dissertation. Realizing that this would take many, many years to accomplish, the student left Teichner's lab with a nervous breakdown. Upon returning after a brief rest, he was strongly motivated to find a better synthetic process. This directly lead to one of the major advances in aerogel science, namely the application of sol-gel chemistry to silica aerogel preparation. This process replaced the sodium silicate used by Kistler with an alkoxysilane, (tetramethyorthosilicate, TMOS). Hydrolyzing TMOS in a solution of methanol produced a gel in one step (called an "alcogel"). This eliminated two of the drawbacks in Kistler's procedure, namely, the water-to-alcohol exchange step and the presence of inorganic salts in the gel. Drying these alcogels under supercritical alcohol conditions produced high-quality silica aerogels. In subsequent years, Teichner's group, and others extended this approach to prepare aerogels of a wide variety of metal oxide aerogels. "

Poor graduate student. I can relate to him, although my ZTP-Al2O3 shortcuts didn't revolutionize anything, and I ended up leaving prior to finishing my thesis. I did, however, still graduate MS.

Lighter-than-air idea

[crow]

What if you made a hollow sphere of aerogel? How large could you make it and still be structurally sound while containing a vacuum? Or perhaps fill it with Helium? Either way, you could make blocks that are lighter than air.

The engineering possibilities...

Re:Old news ....

[nucal]

What's worse is that the student made the breaktrough and all we know is the asshole advisor's name.

Pre-World War II

[Wonko42]

In other news, there's been an astonishing breakthrough in the aerospace industry -- jet-powered aeroplanes! These new jet-planes promise to unite the world as travel times are cut in half across the globe. Stay tuned for more breaking news!