Vital role of nuclear data in space missions

Abstract

NASA has a new vision for space exploration in the 21st Century encompassing a broad range of human and robotic missions including missions to Moon, Mars and beyond. Exposure from the hazards of severe space radiation in deep space long duration missions is a critical design driver. Thus, protection from the hazards of severe space radiation is of paramount importance for the new vision. Accurate risk assessments critically depend on the accuracy of the input information about the interaction of ions with materials, electronics and tissues. A huge amount of essential experimental information of nuclear data for all the ions in space, across the periodic table, for a wide range of energies of several (up to a trillion) orders of magnitude are needed for the radiation protection engineering for space missions that is simply not available (due to the high costs) and probably never will be. One is required to know how every element (and all isotopes of each element) in the periodic table interacts and fragments on every other element in the same table as a function of kinetic energy ranging over many decades. In addition, the accuracy of the input information and database, in general and nuclear data in particular, is very critical and of paramount importance for space exposure assessments particularly in view the agency's vision for deep space exploration. As a result, very accurate and reliable analytical models/tools are needed to describe nuclear interactions that are not available so that radiation risks can be assessed and adequate shielding can be designed. State-of-the-art nuclear cross sections models have been developed at the NASA Langley Research Center. An overview of the vital role and importance of nuclear data for space missions with a couple of examples are discussed.