Space Weathering Experiments on Spacecraft Materials

Abstract

A project to investigate space environment effects on specific materials with interest to remote sensing was initiated in 2016. The goal of the project is to better characterize changes in the optical properties of polymers found in multilayered spacecraft insulation (MLI) induced by electron bombardment. Previous analysis shows that chemical bonds break and potentially reform when exposed to high energy electrons like those seen in orbit. These chemical changes have been shown to alter a material's optical reflectance, among other material properties. This paper presents the initial experimental results of MLI materials exposed to various fluences of high energy electrons, designed to simulate a portion of the geosynchronous Earth orbit (GEO) space environment. It is shown that the spectral reflectance of some of the tested materials changes as a function of electron dose. These results provide an experimental benchmark for analysis of aging effects on satellite systems which can be used to improve remote sensing and space situational awareness. They also provide preliminary analysis on those materials that are most likely to comprise the high areato-mass ratio (HAMR) population of space debris in the geosynchronous orbit environment. Finally, the results presented in this paper serve as a proof of concept for simulated environmental aging of spacecraft polymers that should lead to more experiments using a larger subset of spacecraft materials.

Space Plasma Interactions with Spacecraft Materials

“…For each measurement, an ASD FieldSpec Pro spectroradiometer operating over a 350-2500 nm range collects first a white reference spectrum from a piece of in-vacuum calibrated Spectralon ® . The electron beam is then temporarily extinguished and the motion system moves the integrating sphere to a sample carousel where it measures samples as they are rotated into the measurement position [13].…”

“…The color-color plots were generated using the passbands associated with the r' and i' filters defined by the Sloane Digital Sky Survey [50][51][52][53]. For a more detailed description of the experiment, refer to reference [13].…”

Degradation of the Reflectance Properties of Some GSS in Space, Preliminary Results

“…There have been a huge number of publications and manuscripts on the subject of space materials science [1, 2, 3, etc.]. However, all these papers, with the exception of [4], present theoretical findings or results obtained under laboratory conditions not allowing for the atmospheric effects [5]. The paper by A. Didenko [4] presents experimental data on the spacecraft surfacecoating ageing with time for the period of four and a half years for three types of GSS, namely Horizont, Raduga and Intelsat, obtained during ground-based observations through Earth's atmosphere.…”