Atomic Oxygen Effects on Space Materials in Low Earth Orbit and Its Ground Evaluation

Abstract

The current issues of atomic oxygen (AO) eŠects on space materials in low earth orbit and its ground evaluation techniques are described brie‰y. AO is the dominant gas component at altitudes of 200 600 km. It has abundant energy to break hydrocarbon polymer bonds, thereby causing oxidation and thinning of the polymers through loss of volatile oxidation products. Therefore, ground evaluation of space materials is important. The AO source in Japan Aerospace Exploration Agency (JAXA) is based on laser breakdown phenomena. This source is one of the combined space eŠects test facility, which accommodates the irradiation of independent or coincidental electron beams, ultraviolet rays, and AO. Evaluation of common space materials has been done in addition to researches into new AO protective coatings and materials. As described herein, the AO environment, its interactions with materials, results of space experiments, ground laboratory simulation techniques, and mitigation techniques are presented.