A Geophysical Package for In-situ Planetary Science

Measuring the effect of geological and chemical processes, weather, biological processes and the interaction of SCR and GCR radiation with a planet is fundamental to understanding the formation, evolution and alteration of a planet. This thesis details the evolution and development of a geophysical package that can be used to better understand the effect of these fundamental physical processes by measuring composition, constraining heat flow and measuring the age of a planetary surface. There are a number of future ESA and NASA planetary science missions that are in the planning or initial study phases, where the scientific objectives include determining the surface composition, measuring planetary surface heat flow and constraining planetary chronology. The geophysical package is capable of operation on landers and penetrators; both of these are possible in-situ platforms being proposed for these missions. In addition radioisotope power sources are being proposed for both thermal management and electricity generation; the power source might provide the source of neutrons to induce the γ-ray emission from the planetary surface. The development and verification of a Monte Carlo planetary radiation environment model using both experimental data and data acquired in orbit of the Moon and Mars is described in this thesis. It was used to model the geophysical package on the surface and sub-surface of Mars and Europa. The model was also used to investigate the suitability of several neutron sources to induce γ-ray emission on a planetary surface that could also be used for power generation.