The outer surfaces of spacecraft in geostationary earth orbits are subject to degradation under constant bombardment by cosmic radiation, solar wind, and micro / nanoscale debris. Geostationary orbit is an environment that affects the change in the properties of materials, including atomic oxygen, ultraviolet radiation, thermal cycles, electromagnetic radiation, micrometeorites and man-made orbital particles. The influence of such an environment leads to the fact that spacecraft materials undergo corrosion, erosion, modification of the structure and surface roughness, which degrades the optical, thermal, electrical and mechanical properties. How fast such degradation can be and how it will affect the functioning of spaceships is an urgent problem of our time.
The idea of the project is to study changes in the properties of materials used in the space industry to change the photometric characteristics of geostationary satellites in various spectral ranges. Predictive changes in the properties of satellite coating materials (various films, insulation layers, possibly thin layers of paint, etc.) under the influence of cosmic radiation and orbital collisions will make it possible to estimate the operation time of satellites, in particular, of the Kazsat series.
Program
Task 1 – Analysis of the FAI’s database and obtaining new observational data on multicolour photometry of geostationary satellites.
Working with the FAI photometric archive of multicolour photometry, selecting data for several satellites observed for a sufficiently long time, preferably from the year of launch until the end of the operation, in order to extract information about the change in photometric characteristics, in particular the colour index, over time. AFIF data on observations of the Kazsat-1 and Kazsat-2 spacecraft since launch are one of the important elements in the development of a method for analyzing and modelling the process of changing the colour characteristics of satellite coverage over time.
Task 2 – Create photometric colour indices depending on phase angles, surface shape and composition.
Using the values of the colour index of intact materials available from other sources, we can track their changes over time and develop a method for roughly estimating the lifetime (knowing the lifetime of the observed satellites). To make this possible, we need to solve a direct problem – to determine the photometric indicators of colour depending on phase angles, surface shape and composition. It is necessary to develop programs for visualization and modelling of simple geometric objects for further analysis of their phase portrait, which will serve as the main tool for solving the inverse problem – determining the shape of the satellite and the properties of the reflecting surface using multi-band photometric data. In turn, these characteristics will allow identifying the type of apparatus.
Task 3 – Analysis of degradation and structural changes in materials in the laboratory and numerical modelling of changes in the structure of materials.
Computer simulation of the impact of the space environment, micro-collisions with space debris and micrometeorites on the spacecraft coverage in geostationary orbit. Comparison of archived and new data on satellites of the Kazsat series with the results of numerical simulations.
Expected results:
2020 – Analysis of the entire available database for Kazsat-1 and Kazsat-2. Computer modelling of geometric shapes and determination of their light curve at different phase angles. Adding additional conditions for modelling (coating materials). New data of photometric observations for Kazsat-1 and Kazsat-2.
2021 – Analysis of the impact of space environment conditions on the spacecraft coverage. Computer model showing changes in material structure.
2022 – Analysis of computer modelling of structural changes in materials in laboratory conditions and experimental data on the Kazsat-1 and Kazsat-2 satellites. Prediction of changes in the photometric characteristics of spacecraft coverage under the influence of space radiation and orbital collisions, assessment of the further operation of the satellite.
