German material scientists from Kiel University and the Hamburg University of Technology have created the world’s lightest material, dubbed aerographite. One cubic centimeter of aerographite weighs just 0.2 milligrams, which is four times lighter than the previous record holder, 5,000 times less dense than water, and six times lighter than air.
Aerographite, as you can see from the picture above, is a mesh of carbon tubes, each around 15nm in diameter, interwoven at the micro- and nano-scale level. It is electrically conductive, ductile, jet black (non-transparent), and can withstand high compression and tensile loads. Aerographite can be compressed to a 30th of its original size, gaining extra strength and conductivity in the process, and spring back without any damage to its structure — or it can carry up to 40,000 times its own weight.