NASA's STARDUST mission will capture cometary particles in aerogel similar to those shown here. The unique properties of the aerogel enable the particles to be soft-captured so as to minimize the impact damage and better preserve them for study. This is a scanning electron micrograph (SEM) of a 50 micron glass sphere shot into 0.05 g/cc aerogel at 5 km/s. The cone shaped cap on the spherical projectile is compressed aerogel that built up on the leading edge of the sphere and served as a insulating shield that partially protected the particle.