Developing a Safe Test System for High-energy Electron Flux Environments Testing

Heather Tippets, Brigham Young University Idaho


In order to predict and mitigate adverse environmental effects on spacecraft in orbit about Earth, a versatile pre-launch test capability for assessment and verification of small satellites, systems, and components was developed by Utah State University’s Materials Physics Group. To further diversify this project, a 100 mCi Sr-90 beta radiation source (0.5 MeV – 2.5 MeV) is exploited to simulate the high energy electron flux of geostationary orbit. Various samples including in-the-loop hardware, spacecraft materials, optical components, and solar arrays are irradiated to gain a better understanding of how these materials and electronics break down in space environments. For employee protection, various high and low-Z shielding materials were implemented near the test chamber to minimize X-ray dose rates. In order to forecast employee dose while working around the source, X-ray attenuation through the various shielding materials was calculated. Upon discovering a deficiency in shielding capability, additional lead shielding was implemented to lower dose rates outside of the test chamber to nearly background. Prediction of attenuated dose rates strongly correlate with actual measurements post source installation.