photo credit: NASA/JPL/UW
Aerogel: Comet Dust-Catcher
This photo (hi-res version) shows aerogel, the engineered material that trapped particles from comet Wild 2 (see Aerogel: Catching Comet Dust) as a part of NASA's Stardust probe.
Areogel is a silicon-based solid, like glass, but with a density only about twice that of air. It's an excellent insulator, and a small piece can support a brick (see photo in the NASA Stardust photo gallery). The key to aerogel's properties is its dendritic (branching) structure.
This website, Improbable Research, provides "research that makes people laugh and then think." Links are provided to selected articles from the Journal of Improbable Research and to each year's Ig Nobel Prizes.
While you're on the site, check out "The Biology of B-Movie Monsters," October 31, 2006.