Reading Solar System Science 2020

Lead Research Organisation: University of Reading
Department Name: Meteorology

Abstract

In Reading Solar System Science, we propose five independent projects to gain further insight and understanding in solar and heliospheric physics, magnetospheric plasma processes and planetary atmospheres. Our research will address questions important to how our Sun works, how its variability affects the solar system, the science of space weather, and the existence of life on other planetary bodies.

The solar wind is the term given to the outer atmosphere of the Sun, which is constantly expanding through the solar system and blowing across the planets like a wind. We will use physics-based models and data assimilation to make the first reconstruction of the structure of the solar wind over many decades. This reconstruction can then be probed to discover more about the generation of the solar wind.

The solar wind carries the magnetic field from deep within our star out into the solar system. This field forms closed loops (with both ends at the Sun) and "open" threads, where only one end originates at the Sun. Different independent measures of how much "open" magnetic field exists in the heliosphere provide different estimates of the amount of open field (known as "open solar flux") that exists; we will use a large number of new and old in-situ spacecraft measurements to attempt to explain the discrepancy.

Periodically, the Sun emits large bubbles of plasma into the solar wind, known as coronal mass ejections (CMEs). These bubbles flow through the solar wind, interacting with it and changing shape and speed. We will use imaging data, some of which has been processed by citizen scientists, along with physics-based models to infer the changes in CMEs as they propagate through different solar wind scenarios. We will employ a novel technique to probe how the density of CMEs changes in transit too.

Closer to the Earth, the energetic electrons in the radiation belts that surround the Earth are controlled in part by interactions with a wide range of electromagnetic waves. We have a useful theoretical description of the strength of these wave-particle interactions, but it was only designed for waves that do not vary much in time. Real-world observations indicate that the waves and plasma conditions are highly variable and so we look to run physics-based numerical experiments to identify how we should use our knowledge of wave-particle interactions to better model the behaviour of the radiation belt.

Finally, we will build analogues of the Martian atmosphere in the laboratory in order to better understand the behaviour of charged dust particles and dust devils in the Martian atmosphere. The arid environment of Mars supports the formation of dust devils that are much larger and stronger than those found on Earth, and we propose to recreate conditions for their formation in the lab, in order to better understand how these atmospheric phenomena affect the distribution of methane. Importantly, methane could provide one of the clues to the existence of life on the planet.

Planned Impact

We have identified the following stakeholder groups that will benefit from our research:

Met Office: Through regular funded meetings through the Met Office Academic Partnership (MOAP), we will work closely with the Met Office Space Weather Operations Centre (MOSWOC) to ensure that our science continues to be embedded in their operations with the joint aim to improve and/or extend their operational outputs. The risk of Severe Space Weather is included in the National Risk Register of civil emergencies and MOSWOC exists to provide space weather forecasts and useful information to aid mitigation of this risk in the UK. The Department of Meteorology at the University of Reading is one of only four institutions in the UK in MOAP, providing a clear pathway for knowledge exchange with the Met Office. Of the four Academic Institutions in the partnership, Reading has the greatest range in expertise in the science underlying space weather. Projects 1.1-1.4 address important scientific advances that will enable future improvements to the Met Office's operational outputs.

Power companies and Insurance Underwriters in Space sector: The Department of Meteorology has an extensive network of industry contacts who participate in knowledge exchange through themed meetings hosted at the department, and joint supervision of undergraduate, Masters-level and doctoral projects. Results from projects 1.1-1.4 will be shared with our current industrial partners through regular themed meetings with a view to exploring new, mutually beneficial, research projects in the areas of space weather prediction and mitigation.

International Space Weather Organisations: We engage directly with international space weather organisations in the US such as the Space Weather Predictions Center (with project partner Curt de Koning in Project 1.3), and Predictive Science (in conjunction with Project 1.2) to use our new scientific results to help improve forecasts of extreme space weather events. We plan a number of face to face meetings in order to share results with the aim of improving operational outputs.

School Students: We plan a programme of school visits where staff present new research results and run workshop activities. We will build upon our new scientific results and excitement surrounding upcoming mission launches to create new activities and themed talks. We will add new Space and Planetary activities into our highly successful annual Work Experience program inspired by results from all projects. The Work Experience program in the Department of Meteorology is annually attended by over 40 students from across the South of England, Wales and the Midlands.

Wider Public/space enthusiasts/amateur scientists: Project 1.3 includes data from the highly-successful "Solar Stormwatch" citizen science project which has to date attracted over 20,000 participants. We plan to share our results through the project website to inspire and educate the volunteers, providing an opportunity to discuss the science behind space weather with their peers and expert scientists on discussion boards associated with the project. We will promote the "Solar Stormwatch" project through social media, and it will be hosted free of charge on the popular Zooniverse citizen science platform.

Publications

10 25 50

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Linker J (2021) Coronal Hole Detection and Open Magnetic Flux in The Astrophysical Journal

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Owens M (2021) Extreme Space-Weather Events and the Solar Cycle in Solar Physics

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Owens M (2022) Rate of Change of Large-Scale Solar-Wind Structure in Solar Physics

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Owens M (2023) Annual Variations in the Near-Earth Solar Wind in Solar Physics

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Yardley S (2023) Slow Solar Wind Connection Science during Solar Orbiter's First Close Perihelion Passage in The Astrophysical Journal Supplement Series

 
Description SSA P3-SWE-IV.2: USE OF L5 DATA IN CME PROPAGATION MODELS
Amount € 450,000 (EUR)
Funding ID UKRI/RS02344/TP 
Organisation European Space Agency 
Sector Public
Country France
Start 11/2020 
End 02/2023
 
Description SWEEP - STFC/SWIMMR S4
Amount £450,000 (GBP)
Funding ID ST/V00235X/1 
Organisation Aberystwyth University 
Sector Academic/University
Country United Kingdom
Start 10/2020 
End 06/2023
 
Title Dynamic time warping for solar wind modelling 
Description The structure and dynamics of the magnetospheres of the outer planets, particularly Saturn and Jupiter, have been explored both through remote and in-situ observations. Interpreting these observations often necessitates simultaneous knowledge of the solar-wind conditions impinging on the magnetosphere. Without an available upstream monitor, solar-wind context is typically provided using models initiated with either the output of magnetogram-constrained coronal models or, more commonly, in-situ observations from 1 AU. While 1-AU observations provide a direct measure of solar wind conditions, they are single-point observations and thus require interpolation to provide inputs to outer-heliosphere solar-wind models. In this study we test the different interpolation methods using synthetic 1-AU observations of time-evolving solar-wind structure. The simplest method is "corotation", which assumes solar-wind structure is steady state and rotates with the Sun. This method of reconstruction produces discontinuities in the solar-wind inputs as new observations become available. This can be reduced by corotating both back and forward in time, but this still introduces large errors in the magnitude and timing of solar wind streams. We show how the dynamic time warping (DTW) algorithm can provide around an order-of-magnitude improvement in solar-wind inputs to outer-heliosphere model from in-situ observations near 1 AU. This is intended to build the foundation for further work demonstrating and validating methods to improve inner-boundary conditions to outer-heliosphere solar-wind models, including dealing with solar wind transients and quantifying the improvements at Saturn and Jupiter. 
Type Of Material Computer model/algorithm 
Year Produced 2021 
Provided To Others? Yes  
Impact Too early to say 
URL https://github.com/University-of-Reading-Space-Science/SolarWindInputs_DTW