Would it be possible to make aerogel fully transparent?
Work is being carried out towards this goal. The lack of complete transparency is a result of the variation in the sizes of the particles in the aerogel. The smaller ones are too small to affect the passage of light, but the larger ones cause it to scatter, thus reducing transparency. Therefore, the trick would be to develop a technique that results in pores which are of uniformly small size. One idea which is being studied by NASA is to produce aerogels in space. Tests in low gravity environments have already shown that this results in increased uniformity of pores. However, it will be necessary to find lower cost processes.