Europa radiation environment and monitoring

A summary of the radiation environment and requirements of a Europa Orbiter mission as well as a system-level design for a radiation monitoring facility instrument is presented. The current understanding of the various species of ionizing radiation present at Europa is compiled, offering insight into the aspects relevant for instrument engineering. We argue that the unique and complex nature of the Europa radiation environment both precipitates a need for its further understanding and presents a challenge for its quantification. A review of the use of RadFET sensors is presented for the purpose of highlighting its suitability for a Europa radiation monitor and providing context for the utilization of a radiation monitor on a Europa Orbiter. Finally, new designs are presented for a RadFET facility instrument which utilizes existing scientific instrument interfaces to achieve total dose quantification with a mass and power allocation that does not significantly impact the spacecraft.