The search for life on Europa

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As there is no widely accepted definition of life, the current search within our solar system focuses on the form that we're most familiar with. Previous Europa missions have revealed clear evidence of subsurface oceans most likely sustained by tidal heating and the dynamic radiation environment. Magnetospheric models of the Jovian system suggest a large amount of organic chemistry that has been driven by particles accelerated in Jupiter's magnetic field. This environment likely satisfies the critical requirements for life as we know it.However, the same radiation environment that may support hidden biological processes also pose a threat to future planetary exploration mission payloads. High particle irradiances can affect the performance of detectors/electronic components, significantly reducing the scientific instruments' performance. It is important to model the physical processes involved to fully understand and account for the impact that they will have on overall scientific capability. In 2015, NASA selected the Europa Jupiter System Mission, including Europa Clipper, for the exploration of the moon. Following this, a lander is currently being considered, focussing on the habitability of the moon by verifying the presence on the ocean and its characteristics, whilst determining the geological and biological processes that have and will take place on the moon. The lander will potentially provide an opportunity for the deployment of recently developed analytical instruments to verify the presence of key biological signatures associated with the search for life. Raman spectroscopy is a rapid, non-destructive scattering technique that provides information about the molecular/chemical composition of a sample. Due to recent advances in instrument miniaturisation and robustness, the first Raman spectrometer to be deployed in space will be launched in 2020 as part of the ExoMars rover mission payload. Once on Martian surface, the Raman Laser Spectrometer (RLS) instrument will be used to identify organic compounds and search for signs of life. The development of RLS (and NASA's Mars2020 Raman instruments) has led to a Raman spectrometer being considered as a primary science instrument for NASA's Europa Lander mission. However, effort needs to be focused on improving the overall radiation hardness of Raman instrument designs, through optimising detector performance, radiation mitigation and operating modes.This project involves developing an instrument package for a Europa lander mission (based on typical mission science requirements). The impact that the radiation environment will have on analytical instrument performance (hence the science goals of a mission) will be modelled and investigated. It is also necessary to verify performance of each proposed instrument configuration using radiation environment simulation facilities (experimental) and suitable analogue samples to gain a full understanding of the critical design trade-offs involved.