The Solar Wind and Interplanetary Magnetic Field at Mars

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Unlike the Earth, Jupiter and Saturn, Mars lacks a strong planetary magnetic field. However, the interaction of the ionised Martian upper atmosphere with the supersonic solar wind generates an induced magnetosphere that presents a conductive obstacle to the incoming solar wind and its embedded interplanetary magnetic field (IMF). The resulting solar wind-magnetosphere-ionosphere interactions, modified by the contribution of localised crustal magnetic fields, are quite different to those at strongly magnetized planets and have been the focus of international research over the last two decades.At Earth, continuous solar wind and IMF measurements made at the L1 Lagrange point reveal the energy and mass inputs to the coupled magnetosphere-ionosphere system, controlled strongly by the relative orientation of the interplanetary and terrestrial magnetic fields. However, one of the foremost challenges in understanding the relationships between magnetised solar wind drivers and magnetosphere, ionosphere and atmospheric responses at Mars has been a scarcity of such upstream data. Except for a relatively small number of fortuitous satellite conjunctions, upstream parameters are usually inferred from proxy data, sometimes requiring unrealistic assumptions regarding spatial and/or temporal variability that would be unacceptable in the terrestrial context. In this project the student will assess the credibility and impact of such assumptions and test alternative methodologies through data analysis and modelling. Project goals include:1. To characterise the variability of the quiescent/background solar wind and the embedded IMF at Mars through an analysis of in situ field and plasma measurements.2. To assess how effective current state-of-the-art solar wind/IMF propagation models are at estimating the plasma speed, density and magnetic field properties in the Martian environment.3. To explore new forecasting techniques to provide reliable solar wind and IMF parameters at Mars and other planets.