Solar System Physics

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At Aberystwyth, we are investigating the complex intercouplings of the inner solar system. The Sun, Earth and planets are linked by the interplanetary medium between them. Eruptions from the Sun result in large three-dimensional clouds of plasma which travel at supersonic speeds through interplanetary space. At Earth, they produce geomagnetic storms which disrupt our communications, endanger astronauts and, on the ground, produce compass deflections and, most visibly, the Northern Lights. The same mechanisms that result in a habitable Earth produce effects which shape the surfaces and atmospheres of the inner planets and give rise to the inhospitable conditions on the Moon, Mercury, Venus and, to a lesser extent, Mars. In order to understand these interlinked processes we need to make state of the art measurements of the environments of the Sun, the Planets and the Space in between. These include ground-based measurements and data from space probes both in orbit and on the surfaces of other planets. We can then develop the theories which explain these observations and enable us to predict when they will occur and how strongly they will affect our inner solar system environment. There is a virtuous circle whereby new observations produce new theories, new questions and hence new experimental techniques which allow us to make the next generation of observations. At Aberystwyth, we are world leaders in each of these stages. Our particular strengths are in X-ray and ultraviolet obserations of the Sun and planets, autonomous robots for exploring planetary surfaces and radar techniques to probe near-Earth and interplanetary space. At Aberystwyth we are the lead investigators for the X-ray instrument currently orbiting the Moon on the SMART-1 spacecraft, and its successor on the Indian Chandrayaan-1 mission due to arrive at the Moon in late 2007. We are also playing a leading role in the preparation of the X-ray instruments on the forthcoming BepiColombo mission to Mercury. Our world-leading robotics software would have given Beagle-2 autonomy in making measurements on the surface of Mars and will now be employed when Europe returns to Mars with the upcoming ExoMars mission. Investigators from Aberystwyth are also part of the teams of scientists behind instruments currently orbitting Venus, Mars and the Earth. Aberystwyth is making a unique step forward in probing the the interplanetary medium by observing the twinkling of stars in radar, known as interplanetary scintillation. At the Earth, we apply the technique of tomography, as used in medical scanning, to take snapshots and build three-dimensional pictures of the Earth's ionosphere. Our theory programme concentrates on understanding how the highly dynamic three-dimensional plasma structures can form on the Sun, erupt and accelerate into interplanetary space, and how these rapidly changing structures interact with the magnetic fields, atmospheres and surfaces of the inner planets. By testing our theories at other planets we improve our understanding of the processes which shape our own environment at the Earth. We build computer simulations of these theories which show us the complicated behaviour of the surface and atmosphere of the Sun, plasma clouds in interplanetary space and planetary atmospheres. The University has made a large-investment in the new technology of three-dimensional visualisation and virtual reality which is the only way to truely visualise and understand what is happening. Aberystwyth is unique in our ability to investigate each and every link in the chain of interaction which link the Sun, Earth and Planets. This puts us in an ideal position to understand how events in the inner solar system shape the environment in which we live.