Investigating the Rotation of Sunspots with the Solar Dynamics Observatory

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The aim of this project is to investigate the rotation of sunspots in the solar surface. These rotations, which can last for 10s of days, are an observable consequence of the transfer of magnetic information from the solar interior to the atmosphere. Excess energy stored in the solar atmosphere can be released through eruptions such as solar flares and coronal mass ejections, which can impact us on the Earth.In particular, this project will automate the locating and tracking of sunspots so that sunspot rotations can easily be calculated. Additionally, this will provide information about the relative motions of sunspots within an active region to determine additional sources of energy input (such as shear between sunspots and other magnetic foot point motions) and identify the dominant input mechanisms.The automated approach will be tested against a four-month sample that has already been manually generated. Once this is successful, a larger statistical sample will be generated for scientific exploitation (SDO has an archive of 11 years of continuous data that can be exploited, though analysing the entire catalogue would be a major undertaking in data management, so carefully selected periods will be targeted). This sample will be used to test whether sunspot rotation is a key mechanism for injecting excess energy for (large) solar eruptions, and which other mechanisms may significantly contribute to this process.The project will primarily use data from NASA's Solar Dynamics Observatory (SDO) to identify sunspots and their rotation. SDO provides continuous, high-resolution (in time and space) observations of the solar disk in a range of spectral pass bands that correspond to different layers of the Sun's surface and atmosphere. However, new instrumentation will come online during the PhD period, such as ESA's Solar Orbiter mission, and this will be exploited as appropriate.