Service Module / Space Environment Exposure Device (SM/SEED) is experimental system aboard International Space Station (ISS) to evaluate the degradation of various materials for space application under the Low Earth orbit (LEO) space environment. Three sets of exposure pallets of SM/SEED with the same samples have been exposed to LEO since October 2001. One of the pallets returned to Earth after about one-year exposure. A bonded molybdenum disulfide (MoS2) film was also exposed as a tested material of SM/SEED. The changes in tribological characteristics of the film were examined. And effects of ground-based irradiation with LEO environmental factors (e.g., Atomic Oxygen (AO) and Ultraviolet rays (UV)) were also evaluated. At the beginning of the test, low friction coefficient was observed both in the flight and the AO-irradiated samples. MoO3 was detected from the surface of these samples. A large amount of SiO2 was recognized from the flight sample.
Evaluation of White Paints Exposed to Space Environment on the ISS Russian Service Module / Space Environment Exposure Device