Changes in the Surface and Volume Properties of a Spacecraft during Absorption and Recombination of Oxygen and Nitrogen Atoms

Abstract

The results of studying the influence of cosmic space on a spacecraft surface is presented. We showed that the mechanical (volume and surface), optical, and other characteristics of a spacecraft’s materials noticeably change due to long exposure to cosmic vacuum. At extremely low pressures in cosmic vacuum, the external and internal interfaces in the materials can be broken, resulting in either microscopic surface cracks or internal corrosion. We have shown that changes in the properties of surface layers cause changes in the volume mechanical properties of materials (fatigue strength, etc.). Furthermore, noticeable effects of space vacuum on the mechanical properties of a spacecraft’s materials arise as a result of the absence of oxide and other surface protective films. Due to the disappearance of protective gas and oxide films, and also as a result of sublimation of the surface layers to a thickness close to the wavelengths of electromagnetic radiation, the surface roughness is changed and, as a consequence, their optical characteristics (in particular, the absorption of solar radiation and the emissivity factor) are also changed. During orbital motion in sufficiently dense layers of the upper atmosphere of the Earth, as well as under bombardment by charged particles of cosmic radiation, strong plasma-chemical loosening of the surface material of spacecraft and its dispersion into the surrounding space can occur. This process is especially evident for the front (in the direction of travel) parts of spacecraft. The method used to describe the dynamics of the interaction of atomic oxygen colliding with the surface of silicon dioxide is described. The influence of space vacuum on materials is shown. Particular attention is paid to the phenomenon of accommodation of low-orbit satellite systems and the use of information received from satellites.