Fun fact: this stuff is called aerogel and it is probably one of the coolest man-made materials ever. Aerogels are some of the world’s lightest solid materials, as they are composed of 99.98% air by volume. X-Aerogel structures are super strong, graphene aerogels are the world’s lightest solid, and silica aerogels are the best thermal insulators on the planet. Aerogels have countless practical applications, including being used by NASA for thermal insulation in the Mars Rover and in space suits.
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