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The hazard of UV-induced oxidation to solar-viewing spacecraft optics



Charles S. Tarrio, Robert F. Berg, Thomas B. Lucatorto, Dale E. Newbury, Nicholas Ritchie, Andrew Jones, Frank Eparvier


The two most prevalent outgas contaminants on satellites are organic molecules and water vapor. Adsorbed organic molecules can degrade a solar-viewing instrument when they are cracked by ultraviolet radiation (UV) and become a light-absorbing layer of carbon. In an earlier work we examined the transmission loss of the extreme-ultraviolet (EUV) aluminum filters used onboard the Solar Dynamics Observatory, and we showed that the degradation was not caused by carbonization. Here, by comparing the losses of the satellite filters with the losses induced on similar filters by synchrotron radiation, we demonstrate that the degradation was likely due to oxidation caused by the ultraviolet activation of adsorbed water vapor.
Solar Physics


Oxidation, Cabrera-Mott model, spacecraft optics, instrument degradation


Tarrio, C. , Berg, R. , Lucatorto, T. , Newbury, D. , Ritchie, N. , Jones, A. and Eparvier, F. (2023), The hazard of UV-induced oxidation to solar-viewing spacecraft optics, Solar Physics, [online],, (Accessed April 16, 2024)
Created March 2, 2023