Aerogel is a manufactured material with the lowest bulk density of any known porous solid. It is derived from a gel in which the liquid component of the gel has been replaced with a gas. The result is an extremely low-density solid with several remarkable properties, most notably its effectiveness as a thermal insulator. It is nicknamed frozen smoke, solid smoke, solid air or blue smoke due to its translucent nature and the way light scatters in the material.
Aerogel
