Andrew J. Zillmer

Radiation Environments and Exposure Considerations for the Multi‐Mission Radioisotope Thermoelectric Generator

The Multi‐Mission Radioisotope Thermoelectric Generator (MMRTG) is the next generation (RTG) being developed by DOE to provide reliable, long‐life electric power for NASA’s planetary exploration programs. The MMRTG is being developed by Pratt & Whitney Rocketdyne and Teledyne Energy Systems Incorporated (TESI) for use on currently planned and projected flyby, orbital and planet landing missions. This is a significant departure from the design philosophy of the past which was to match specific mission requirements to RTG design capabilities. Undefined mission requirements provide a challenge to system designers by forcing them to put a design envelope around “all possible missions”. These multi‐mission requirements include internal and external radiation sources. Internal sources include the particles ejected by decaying Pu‐238 and its daughters plus particles resulting from the interaction of these particles with other MMRTG materials. External sources include the full spectrum of charged particle radiati...