Coloration of Glasses Induced by Space Ionizing Radiation

The optical stabilities of several glasses (K9―HL glass, JGS3 silica glass, K509 glass and JGS1 silica glass) under conditions of ionizing radiation (proton flux, electron flux) were studied. Additionally, using the simulation results of space ionizing radiation by SPENVIS and CR?ME―MC, optical lives of these four glasses serving in a given orbital (perigee 350 km, apogee 425 km, orbital inclination 51.6o) were analysed. It can be found that being used for more than 10 years in this given orbital, the optical transmission of the K9―HL glass evidently decreased, while the optical transmission of the other three glasses (JGS3 silica glass, K509 glass and JGS1 silica glass) didn’t change or changed a little and they can serve as good optical materials in the given space orbital. Because most of the space particles (ionizing radiation) can be effectively inhibited or absorbed in some penetration depth of the glass, the space ionizing radiation can only color a surface layer of the glass, as a result, an anti―radiation glass layer can be put outside the window of a long duration spacecraft in order to reduce ionizing irradiation, and the layer can be made of silica glass.