Atomic Oxygen: The Hidden Material Menace in Low Earth Orbit

Atomic oxygen in low Earth orbit aggressively erodes carbon-based polymers, carbon composites, and optical surfaces on spacecraft such as the ISS. NASA tests exposed material trays outside the station to study damage and variations in material properties, leading to protective coatings like silicon dioxide or aluminum oxide to mitigate reactions with single oxygen atoms. In LEO, the atmosphere is a thin, UV-driven environment rather than a hard vacuum, so long-duration missions require careful material selection and protective measures; very low orbits demand extra care for satellites. Deep space exposure to atomic oxygen is much less of a concern, making this primarily a LEO issue.