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Discovered in the thirties, aerogels rank today among the lightest solids known and display outstanding thermal, optical and acoustic properties in air and vacuum due to their highly porous open-cell structure. Absence of convection driven by density gradients prior to gelation as well as reduction of sedimentation are examined as possible means to affect the nanometer scale pore structure. A microgravity experiment has been designed and is in preparation for a space shuttle flight in 1999.