A Consolidated Grant Proposal for Solar and Planetary Science at the University of Leicester, 2019 - 2022

We propose a world-class programme of research that focuses on two main areas of study concerned with our solar system. The first involves study of the outer environments of the planets where the gas is in the plasma (ionized) state, such that it not only feels the gravitational pull of the planet, but also interacts strongly with its magnetic field. In the second area we seek to study the origin and development of solar system bodies, and the impact on the evolution of life, through detailed examination of the composition of samples from Mars, which will provide information on the way in which the surface of the planet has evolved, interactions with water, and interactions between surface and the atmosphere. Previous work in the first area shows that the outer environments of the planets vary widely, determined by the interaction with the plasma wind that blows continuously from the Sun on the outside, and the interaction with the planet and its moons on the inside. The solar wind is prone to outbursts that can lead to magnetic storms and bright auroras at Earth, as well as varying strongly over the 11-year solar cycle, and with distance from the Sun. Its interaction with the planets then depends on whether the planet is magnetised, has an atmosphere, and has active moons orbiting close in. We will use spacecraft data to study Mercury close to the Sun that has a magnetic field but almost no atmosphere (MESSENGER mission), Mars further away that has an atmosphere but no strong magnetic field to prevent its erosion by the solar wind (Mars Express and MAVEN), and Earth at intermediate distances having both an atmosphere and a magnetic field (using data from a number of missions (Iridium satellite constellation, van Allen probes, Arase) and ground based facilities (SuperDARN and SuperMAG). We will also study the strongly magnetized giant planets Jupiter and Saturn using data from the new Juno mission at Jupiter and Cassini at Saturn, combined with observations of the auroras at ultraviolet wavelengths using the Hubble Space Telescope and at infrared wavelengths using large ground-based telescopes. Auroras are caused by large-scale electric currents flowing between the outer environments and the upper ionized atmospheres, which communicate force between these regions. Overall emphasis will be on the complex physical processes that couple the solar wind on the outside, the magnetic field surrounding the planet (if any), and the planetary atmosphere or surface on the inside. Finally, using a combination of electron microscopy and synchrotron-based X-ray spectroscopy of meteorites and experiments on analogue-fluid reactions, we will provide the most detailed mineralogical analyses and formation models of martian meteorite carbonates and co-existing clays. From this, we will address the nature of martian hydrothermal crustal fluids, and test associated current models for the ancient atmosphere. Thirdly, key processes in the formation of the martian igneous crust, in particular the formation of the main melt types, will be constrained by modelling meteorite and lander data, enabling comparisons to differentiation on other planets.