Aerogel, developed in the
1930s, is 99.9% air and 0.1% silica dioxide. It's often referred to
as "frozen smoke" due to its phantom-like appearance. Its incredibly
large internal surface area means that a sugar cube size volume of the
stuff would "unfold" to fill the area of a football field. Aerogel can
support tremendous weight for its mass and provides 39 times the insulation
rating as fiberglass. It is so fragile that it has to be handled with
gloves to avoid permanent fingerprinting.