Solar proton radiation during an interplanetary space mission

Abstract

SEPs events are a serious hazard for both spacecraft and humans during interplanetary space missions. In this work, we use the ESA's SEPEM tool for statistical modelling the cumulative and the worst case proton fluences over the missions Helios 1 and Helios 2. We compute their energy spectra for periods of the solar cycle over the mission duration and fit them to most common distributions. We analyse the best fitting function for each case. Finally, we compare the cumulative fluence energy spectra of the model results at a 90% confidence level with data measured by the Helios 1 and 2 spacecraft.