Aerogelis a syntheticporous ultralight materialderived from a gel, in which the liquidcomponent of the gel has been replaced with a gas. The result is a solid with extremely low density [ 1 ]and low thermal conductivity. Nicknames include "frozen smoke", [ 2 ]"solid smoke", "solid air" or "blue smoke" owing to its translucentnature and the way light scattersin the material. It feels like fragile expanded polystyrene( Styrofoam) to the touch. Aerogel was first created by Samuel Stephens Kistlerin 1931, as a result of a bet with Charles Learned over who could replace the liquid in "jellies" with gas without causing shrinkage. [ 3 ] [ 4 ] Aerogels are produced by extracting the liquid component of a gel through supercritical drying. This allows the liquid to be slowly dried off without causing the solid matrix in the gel to collapse from capillary action, as would happen with conventional evaporation. The first aerogels were produced from silica gels. Kistler's later work involved aerogels based on alumina, chromiaand tin dioxide. Carbonaerogels were first developed in the late 1980s.