Via sciam.com -
Almost as light as air, capable of withstanding a direct flame or catching speeding comet dust like a baseball mitt stops a hardball, aerogels are some of the strangest solids in the world. This "Space Age Styrofoam" was developed in a chemistry lab decades ago but is now appearing in snowsuits, explosives and even energy storage technology.
Aerogels are the lightest and lowest-density class of materials in the world. Up to 99 percent of the dry, rigid gels are air, while the rest consists of silica, carbon, metals and other substances; it feels like a Styrofoam peanut. Yet, some formulations can support close to two thousand times their weight (if it is lowered onto them slowly). "Enough force to crush a Rice Krispie will crush an aerogel," states Stephen Steiner, a nanomaterials graduate student at the Massachusetts Institute of Technology and aerogel researcher.
But when NASA needed something to safely capture particles from Comet Wild 2 traveling at 6,000 meters per second as part of its recent Stardust Mission, the agency turned to the airy substance. A grid of silica aerogel within the spacecraft was able to catch the minuscule particles (smaller than a grain of sand) without damaging them in any way.
In addition, NASA's Mars Rovers were lined with the ultrainsulating material. Silica and carbon aerogels are poor thermal conductors, because there "isn't much matter there to do the job," according to Steiner. The porous, kitchen-sponge-like structure of aerogel forms a labyrinth through which it is nearly impossible for air molecules--and sound waves--to travel. Therefore, silica aerogel can protect a human hand from the direct heat of a blowtorch as well as dampen its roaring sound.
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Now that is what I call "technosorcery"...very cool.
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