Evaluation of White Paints Exposed to Space Environment on the ISS Russian Service Module / Space Environment Exposure Device

White paints are used as thermal-control materials for spacecraft, often on complexly shaped structures on which it is difficult to apply multi-layer insulators. They present advantages over most polymeric films (single or multi-layer insulation) because they are more stable against atomic oxygen. Atomic oxygen in a low earth orbit environment strikes spacecraft and chemically reacts with materials, producing erosion or oxidation. JAXA has conducted space exposure experiments using the Space Environment Exposure Device on the Russian Service Module in the International Space Station to evaluate the tolerance of materials in a low earth orbit. Silicone-based white paints were exposed on the device for three different exposure periods, demonstrating high resistance. Silicon contaminants were observed on the retrieved paint surfaces.