Design Considerations and Test Facilities for Accelerated Radiation Effects Testing*

Outer planet missions require electronics and science instruments that have a useful lifetime of up to ten years. During this time, they are continuously within the gamma and neutron fields of the radioisotope thermoelectric generator (RTG), which provides electrical power to the spacecraft. Additionally, these electronics and science instruments are subjected to a number of other radiation stresses: Jovian radiation belts, solar flares, solar wind and cosmic radiation. One means of verifying the adequacy of components and of design for the ten-year useful lifetime is by accelerated testing in an adequately simulated environment. The intent is to simulate, in a short testing period, the effects to be expected in the real spacecraft mission, taking into account all of the stresses involved in radiationcryogenic-vacuum environments.