Satellite Radiation Risk Forecasts (Sat-Risk)

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SummaryOur society relies on satellites more than ever before, from the use of mobile phones to broadcasting and Earth observation. The use of GPS navigation, positioning and timing signals has grown considerably and we now use these signals in ways that were never foreseen, for example in agriculture and stock market trading. The modern world has also become more connected and built up dependencies that are no longer clearly identifiable. It is therefore essential that we take every reasonable precaution to ensure that satellites are protected.Space Weather poses one of the most important threats to satellites in orbit, primarily through radiation exposure. Radiation exposure can increase within a few minutes, by a ten thousand fold or more, and remain high for days, even months. For example, in 2003 during a large space weather event known as the Halloween storm radiation levels were highly disturbed and approximately 10% of the entire satellite fleet were affected by satellite anomalies (malfunctions) leading to service interruption and in one case the complete loss of a scientific satellite costing $640 million (Cannon et al., 2013). In 2012 the UK Government recognised the importance of space weather as a low frequency high impact event and included it on the National Risk Register (Cabinet Office, 2012). This was revised in 2017 with a recommendation for more investment into forecasting as a means of mitigating the impact. More recent research suggests that with current forecasting capability the loss of gross domestic product to the UK would be around £2.9 billion but with more investment in enhanced forecasting this could be reduced to £0.9 billion (Oughton et al., 2019). The purpose of this proposal is to provide enhanced forecasting to help reduce the impact on satellites. Currently there are over 2,200 operational satellites in orbit (December 2019).This proposal brings together scientists from across the UK with stakeholders from the UK Met Office. The goal is to develop a real-time system to forecast radiation exposure to satellites for a range of different orbits, and quantify the risk of damage or degradation. We will do this by taking research models of the Earth's radiation belts - regions of high energy electrons and protons trapped by the external geomagnetic field and which circulate around the Earth - and turn them into operational forecasting models. The models will use real-time data from ground and space to forecast radiation exposure up to 24 hours ahead for different orbits, including geostationary orbit, Low Earth orbit and medium Earth orbit. It will also include data on radiation storms and cosmic rays. The particle radiation levels will then be used to calculate the damaging radiation effects on electronic components and solar arrays and compared to design guidelines to assess the risk of damage. The project will also include four research elements which are specifically targeted at reducing the uncertainty in the forecasts. The project will deliver a world leading forecasting capability for the Met Office that will help satellite operators take mitigating action, help satellite designers develop more resilient design and space insurance reduce the risk of loss. It will also support the growth of the satellite industry and the UK National Risk Register.1. Cannon, P, S., et al. (2013), Extreme Space Weather: Impacts on Engineered Systems and Infrastructure, Royal Academy of Engineering, London, SW1A 2WH.2. Cabinet Office, (2012), National risk register of civil emergencies, Whitehall, London SW1A 2WH, www.cabinetoffice.gov.uk3. Oughton et al., (2019), A Risk Assessment Framework for the Socioeconomic Impacts of Electricity Transmission Infrastructure Failure Due to Space Weather: An Application to the United Kingdom, Risk Analysis, https://doi.org/10.1111/risa.13229