The Effect of Products Released from the Structural Materials of a Spacecraft on the Optical Properties of Its Thermal Control Coatings

In this paper, we report on our experimental findings regarding the release of easily condensing substances from certain structural materials utilized in spacecraft, and we evaluate the impact of thin condensate films on the integral optical coefficients of external thermal control coatings (TCCs) of spacecraft. To simulate the space environment and solar radiation, the experiments were conducted in a vacuum. We found that the flux densities of the components released from the materials’ surfaces reach 5.4 × 10–7 g cm–2 s–1 and exhibit an exponential decrease over time. Furthermore, thin condensate films with a thickness of 100 Å can significantly degrade the integral optical coefficients of TCCs by tens of percent. These effects can alter the heat balance of the spacecraft. The experimental research methods used in this study can be applied to a broad range of materials, and the results have implications for the design and construction of various types of spacecraft.