A breakthrough technology is one that breaks through the dam of conventional wisdom and slow progress, opening up prospects for transformative change. The radical novelty of a "breakthrough technology" is thus conveyed by the old, familiar, and rather conventional image of a "breakthrough". This holds true for nanotechnology's claim to novelty. It has to draw on traditional imagery that, through redeployment in a novel context, acquires new meaning. Nanotechnology is shaping the world atom by atom. This article gives an overview of nanotechnology in space.