Solar System Physics at Aberystwyth University

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The Solar System Physics (SSP) group at Aberystwyth University has research interests extending from the solar interior, through the solar atmosphere and interplanetary space, to Earth and planetary ionospheres. These are important aspects of our solar system, and our study of these environments leads to progress in physics and astronomy, direct benefits to society in understanding the hazards of space weather and asteroid impacts, and other indirect benefits through cross-disciplinary research.A strong magnetic field permeates the Sun's visible surface (photosphere), and dictates the structure of the atmosphere. This is the corona - a hot, magnetised plasma, an interesting environment for physics. Understanding this environment, through observation and models, drives progress on fundamental plasma physics, and leads to the ability to predict solar storms. Models of this complex system remain incomplete or untested, thus many aspects remain unexplained. With advancements in observation, solar physics is on the verge of answering some of these questions. Our research plays an important part in this effort.We know that the solar magnetic field emerges from the interior in strong tubes of closely-packed fieldlines, akin to ropes. These appear as sunspots on the photosphere. We study the behaviour of sunspots as they rotate with the Sun across the visible disk, in order to understand the transport of the magnetic field and energy from the interior into space. As huge solar telescopes are planned and built we must have the necessary software tools to interpret and analyse new data. In preparation, we are creating model spectra of molecules which exist in the relatively cool environment of sunspots. Solar observations of spectral lines from these molecules help probe the sunspot environment, giving constraints on physical properties such as temperature or magnetic field. Part of this effort involves the research input of A-level school students - a rare chance to combine cutting-edge research with the engagement and education of the next generation of scientists.We are dedicated to the development of new data analysis tools that reveal and characterise solar atmospheric events and phenomena. For the first time, our methods have revealed a stream of faint disturbances moving everywhere, continuously through the corona. This provides a powerful new diagnostic that will constrain models and enable the mapping of the intricate coronal magnetic field. Our advanced numerical models are revealing the complex interplay between twists in the magnetic field and plasma flows along the field - ultimately helping us to understand events such as large eruptions that can hit and effect Earth. Our methods have cross-disciplinary applications. For example, software developed by the group to detect and track solar storms has recently been used to improve the diagnostics of microscope time-series imagery of cancer cell growths.Clues to the complex plasma processes in the corona and beyond lie in direct measurements of the solar wind plasma by multiple spacecraft. We are developing new analysis tools to interpret these measurements, allowing a more complete picture of the history of the solar wind as it evolves from the Sun to Earth. This leads to an understanding of the processes that heat and accelerate the plasma near the Sun and to an understanding of what important processes occur in tenuous magnetic plasmas, of broad general importance to physics and astronomy. Observed changes in the lunar surface may be due to impacts, or to lunar internal activity. We have leading processing methods to identify and analyse events. Categorizing large number of events will be achieved with the help of citizen scientists. This effort is important to understand geological processes on the Moon, and from a more practical standpoint, to identify the safest sites for future exploration. Our methods can also be used for other airless planets.