Analogue Studies for In Situ Surface Planetary Exploration.

Analogue studies importantly underpin planetary missions and can provide essential continuity between payload development and actual mission operations. This thesis focuses on three topics related to analogue studies, namely planetary analogue materials, analogue experiments and the application of scientific autonomy for robotic missions. The common theme of the work relates to field geology on Mars and the search for life (astrobiology). Examples of astrobiology-related missions to Mars are described to illustrate what has been undertaken so far and what strategies are planned for the future, including where and how one might look for signs of past and present life. A range of in situ techniques essential for planetary field geology are reviewed including imaging (multi-scale), analytical measurements (spectroscopy) and geotechnics (physical interaction with surface materials). A comprehensive specimen archive and associated experiment database called GSPARC (Geological Specimen Archive) is described. Samples from the archive were used in the experimental part of this thesis. Two mission-like studies were undertaken based on the ability of a combination of imaging and spectroscopic techniques (X-ray, Mössbauer and Raman) to unambiguously identify morphological biosignatures and to assess the biogenic potential of sedimentary structures in ancient rocks. The techniques employed confirmed their effectiveness for in situ astrobiology when used collectively. Empowering planetary robots with scientific autonomy has the potential to increase science return and extend ground coverage. To address these desires, a novel approach to autonomous science operations is defined and the results from robotic trials using an early implementation of the concept showed that basic geological parameters can be recognised, appropriately scored and used to influence operations. The need for further work within each of the topics is argued and recommendations are made to ensure the continuation of an integrated programme of analogue studies. Spin-off potential to other areas of science is highlighted.