The Search for Life: Development of an Analytical Camera System for Space Applications
thesisposted on 01.08.2019, 10:20 by Hannah N. Lerman
Since the first detailed observations made by the Voyager probe, Jupiter’s moon Europa has been a key target for astrobiological exploration. Previous missions have provided evidence of a subsurface ocean, source of internal heating and geological activity. This evidence, with recent developments in instrument technology, has resulted in space agencies focusing their efforts on the exploration of Europa. The next generation of landers will aim to assess Europa’s habitability and capacity to support life using analytical instruments (e.g. Raman and UV-Vis fluorescence spectrometers). To achieve the science goals of the mission, these instruments will be required to operate effectively in extreme temperature and radiation conditions. In preparation for Europa lander missions, this thesis presents the development of a multi-analytical technique camera system suitable for operation on Europa. It describes the current CCD and CMOS detector systems, outlines key performance characteristics, how they address science requirements of future missions, and highlights challenges associated with harsh environments. It presents the use of a Monte Carlo simulation replicating spectral output of a detector system in extreme radiation conditions to predict, evaluate and optimise system performance. Details of proton irradiation campaigns are provided, along with analysis of the resulting camera performance. Suggestions are given for design, architecture and operating modes to ensure reliable data acquisition capable of achieving mission goals. Using analytical spectroscopy studies, instrument sensitivity levels were assessed using Europan analogue samples. Spectra acquired during a field campaign to a planetary analogue site and data acquired using existing flight instrument (ExoMars) prototypes are presented and used to assess performance of systems in a Europa-like environment. Outlined are the need for combined analytical techniques when considering mission science goals and strict engineering requirements, the development of a novel quadrant detector system capable of performing Raman, UV fluorescence and X-ray fluorescence spectroscopy and context imaging.