MIST

Magnetosphere, Ionosphere and Solar-Terrestrial

Latest news

Charter amendment and MIST Council elections open

Nominations for MIST Council open today and run through to 8 August 2021! Please feel free to put yourself forward for election – the voting will open shortly after the deadline and run through to the end of August. The positions available are:

  • 2 members of MIST Council
  • 1 student representative (pending the amendment below passing)

Please email nominations to This email address is being protected from spambots. You need JavaScript enabled to view it. by 8 August 2021. Thank you!

Charter amendment

We also move to amend the following articles of the MIST Charter as demonstrated below. Bold type indicates additions and struck text indicates deletions. Please respond to the email on the MIST mailing list before 8 August 2021 if you would like to object to the amendment; MIST Charter provides that it will pass if less than 10% of the mailing list opposes its passing. 

4.1  MIST council is the collective term for the officers of MIST and consists of six individuals and one student representative from the MIST community.

5.1 Members of MIST council serve terms of three years, except for the student representative who serves a term of one year.

5.2 Elections will be announced at the Spring MIST meeting and voting must begin within two months of the Spring MIST meeting. Two slots on MIST council will be open in a given normal election year, alongside the student representative.

5.10 Candidates for student representative must not have submitted their PhD thesis at the time that nominations close.

SSAP roadmap update

The STFC Solar System Advisory Panel (SSAP) is undertaking a review of the "Roadmap for Solar System Research", to be presented to STFC Science Board later this year. This is expected to be a substantial update of the Roadmap, as the last full review was carried out in 2012, with a light-touch update in 2015.

The current version of the SSAP Roadmap can be found here.

In carrying out this review, we will take into account changes in the international landscape, and advances in instrumentation, technology, theory, and modelling work. 

As such, we solicit your input and comments on the existing roadmap and any material we should consider in this revision. This consultation will close on Wednesday 14 July 2021 and SSAP will try to give a preliminary assessment of findings at NAM.

This consultation is seeking the view of all members of our community and we particularly encourage early career researchers to respond. Specifically, we invite:

Comments and input on the current "Roadmap for Solar System Research" via the survey by clicking here.

Short "white papers" on science investigations (including space missions, ground-based experimental facilities, or computing infrastructure) and impact and knowledge exchange (e.g. societal and community impact, technology development). Please use the pro-forma sent to the MIST mailing list and send your response to This email address is being protected from spambots. You need JavaScript enabled to view it..

Quo vadis interim board

 

A white paper called "Quo vadis, European space weather community" has been published in J. Space Weather Space Clim. which outlines plans for the creation of an organisation to represent the European space weather community.
Since it was published, an online event of the same name was organised on 17 March 2021. A “Quo Vadis Interim Board” was then set up, to establish a mechanism for this discussion, which will go on until June 21st.

The Interim Board is composed of volunteers from the community in Europe. Its role is to coordinate the efforts so that the space weather (and including space climate) European community can:

  1. Organise itself
  2. Elect people to represent them

To reach this goal, the Interim Board is inviting anyone interested in and outside Europe to join the “Quo Vadis European Space Weather Community ” discussion forum.

Eligible European Space Weather Community members should register to the “Electoral Census” to be able to vote in June for the final choice of organisation.

This effort will be achieved through different actions indicated on the Quo Vadis webpage and special Slack workspace.

Call for applications for STFC Public Engagement Early-Career Researcher Forum

 

The STFC Public Engagement Early-Career Researcher Forum (the ‘PEER Forum’) will support talented scientists and engineers in the early stages of their career to develop their public engagement and outreach goals, to ensure the next generation of STFC scientists and engineers continue to deliver the highest quality of purposeful, audience-driven public engagement.

Applications are being taken until 4pm on 3 June 2021. If you would like to apply, visit the PEER Forum website, and if you have queries This email address is being protected from spambots. You need JavaScript enabled to view it..

The PEER Forum aims:

  • To foster peer learning and support between early career scientists and engineers with similar passion for public engagement and outreach, thus developing a peer support network that goes beyond an individual’s term in the forum 
  • To foster a better knowledge and understanding of the support mechanisms available from STFC and other organisations, including funding mechanisms, evaluation, and reporting. As well as how to successfully access and utilise this support 
  • To explore the realities of delivering and leading public engagement as an early career professional and build an evidence base to inform and influence STFC and by extension UKRI’s approaches to public engagement, giving an effective voice to early career researchers

What will participation in the Forum involve?

Participants in the PEER Forum will meet face-to-face at least twice per year to share learning and to participate in session that will strengthen the depth and breadth of their understanding of public engagement and outreach.

Who can apply to join the Forum?

The PEER Forum is for practising early-career scientists and engineers who have passion and ambition for carrying out excellent public engagement alongside, and complementary to, their career in science or engineering. We are seeking Forum members from across the breadth of STFC’s pure and applied science and technology remit.

The specific personal requirements of PEER Forum membership are that members:

  • Have completed (or currently studying for – including apprentices and PhD students) their highest level of academic qualification within the last ten years (not including any career breaks)
  • Are employed at a Higher Education Institute, or a research-intensive Public Sector Research Organisation or Research Laboratory (including STFC’s own national laboratories)
  • Work within a science and technology field in STFC’s remit, or with a strong inter-disciplinary connection to STFC’s remit, or use an STFC facility to enable their own research
  • Clearly describe their track record of experience in their field, corresponding to the length of their career to date
  • Clearly describe their track record of delivering and leading, or seeking the opportunity to lead, public engagement and/or outreach
  • Can provide insight into their experiences in public engagement and/or outreach and also evidence one or more of
  • Inspiring others
  • Delivering impact
  • Demonstrating creativity
  • Introducing transformative ideas and/or inventions
  • Building and sustaining collaborations/networks
  • Are keen communicators with a willingness to contribute to the success of a UK-wide network
  • https://stfc.ukri.org/public-engagement/training-and-support/peer-forum/  

    Astronet Science Vision & Infrastructure Roadmap

     

    Astronet is a consortium of European funding agencies, established for the purpose of providing advice on long-term planning and development of European Astronomy. Setup in 2005, its members include most of the major European astronomy nations, with associated links to the European Space Agency, the European Southern Observatory, SKA, and the European Astronomical Society, among others. The purpose of the Science Vision and Infrastructure Roadmap is to deliver a coordinated vision covering the entire breadth of astronomical research, from the origin and early development of the Universe to our own solar system.

    The first European Science Vision and Infrastructure Roadmap for Astronomy was created by Astronet, using EU funds, in 2008/09, and updated in 2014/15. Astronet is now developing a new Science Vision & Infrastructure Roadmap, in a single document with an outlook for the next 20 years. A delivery date to European funding agencies of mid-2021 is anticipated. 

    The Science Vision and Infrastructure Roadmap revolves around the research themes listed below:

    • Origin and evolution of the Universe
    • Formation and evolution of galaxies
    • Formation & evolution of stars
    • Formation & evolution of planetary systems
    • Understanding the solar system and conditions for life

    but will include cross-cutting aspects such as computing and training and sustainability.

     

    After some delays due to the global pandemic, the first drafts of the chapters for the document are now available from the Panels asked to draft them, for you to view and comment on. For the Science Vision & Roadmap to be truly representative it is essential we take account of the views of as much of the European astronomy and space science community as possible – so your input is really valued by the Panels and Astronet. Please leave any comments, feedback or questions on the site by 1 May 2021.

    It is intended that a virtual “town hall” style event will be held in late Spring 2021, where an update on the project and responses to the feedback will be provided.

    Nuggets of MIST science, summarising recent papers from the UK MIST community in a bitesize format.

    If you would like to submit a nugget, please contact This email address is being protected from spambots. You need JavaScript enabled to view it. and we will arrange a slot for you in the schedule. Nuggets should be 100–300 words long, include a figure/animation, and include an affiliation with a UK MIST institute. Please get in touch!

    Multi‐scale observation of two polar cap arcs occurring on different magnetic field topologies

    By Jade Reidy (University of Southampton & British Antarctic Survey)

    Polar cap arcs (auroral arcs occurring at high latitudes) have been under debate since they were first discovered over 100 years ago. Although reports present conflicting evidence of the arcs forming on open field lines whilst others argue they are formed on closed field lines, recent work suggests that more than one polar cap arc formation mechanism potentially exists (e.g. Reidy et al., 2017, 2018).

    Two events containing polar cap arcs occurring over Svalbard have been investigated using multiscale ground‐based and spacecraft instrumentation. Figures 1a and 2a show UV images from each event from the Special Sensor Ultra-Violet Imager (SSUSI) on board low-orbiting spacecraft (DMSP). These auroral images have been projected onto magnetic local time grids with noon at the top and dawn to the right. On both SSUSI images, we have projected an all sky camera image from Svalbard; this demonstrates how the ground-based and global-scale observations are related and allowed us to find an interval where the arc passes through the small field of view of the Auroral Structure and Kinetics (ASK) instrument (shown in Figures 1b and 2b for each event). Key features of each event are summarised below:

    Event 1 – A Closed Event

    • Electron and ion precipitation observed in both hemispheres.
    • Highly dynamic small scale structure is observed (Figure 1b), similar to features in the main auroral oval.

    Spacecraft and ground-based images of the auroral arc showing both the global structure and the small-scale structuring.

    Figure 1: Observations of the polar cap arc occurring on 04 February 2016. (a) SSUSI and the all sky imager observations. (b) ASK instrument observations of the auroral arc.

    Event 2 – An Open Event

    • An electron-only particle signature.
    • Very dim auroral features that are consistent with the low plasma density of the magnetotail lobes (Figure 2b).

    Spacecraft and ground-based images of the auroral arc showing both the global structure and the small-scale structuring.

    Figure 2: Observations of the polar cap arc occurring on 15 December 2015, in the same format as Figure 1.

    In the full paper we investigate the different formation mechanisms further by comparing to observations from different instrumentation (including a ground-based spectrograph, located on Svalbard, and the Super Dual Auroral Radar Network). We conclude both events to be consistent with different and distinct formation mechanisms and that this is reflected in the small scale observations.

    Please see the paper for full details:

    Reidy, J. A.,  Fear, R. C.,  Whiter, D. K.,  Lanchester, B. S.,  Kavanagh, A. J.,  Price, D. J., et al. (2020).  Multi‐scale observation of two polar cap arcs occurring on different magnetic field topologies. Journal of Geophysical Research: Space Physics,  125, e2019JA027611. https://doi.org/10.1029/2019JA027611

    Dipole Tilt Effect on Magnetopause Reconnection and the Steady‐State Magnetosphere‐Ionosphere System: Global MHD Simulations

    By Joseph Eggington (Imperial College London)

    The Earth's dipole axis is tilted with respect to the Sun; the extent of this tilt, given by the ‘dipole tilt angle’, changes both diurnally and seasonally as the planet orbits and rotates. This introduces numerous variabilities in the coupled magnetosphere‐ionosphere system, such as altering the location and intensity of magnetic reconnection, allowing the tilt angle to strongly influence magnetospheric convection. In this study, we perform global magnetohydrodynamic (MHD) simulations of the steady‐state magnetosphere‐ionosphere system using the Gorgon MHD code. We drive the system with purely southward Interplanetary Magnetic Field (IMF) conditions for tilt angles from 0–90°, exploring hypothetical configurations beyond the actual extreme of ~30° to elucidate the underlying tilt angle dependence of the system. We identify the location of the magnetic separator (the 3-D reconnection X-line) with increasing tilt angle, showing how the shift of the separator southward on the magnetopause and the resulting changes in the reconnection rate lead to weaker and more time-dependent coupling with the solar wind at large tilt angles.

    These trends map down to the ionosphere, with the polar cap contracting as the tilt angle increases, and the region I field‐aligned current (FAC) system migrating to higher latitudes with changing morphology. As shown in the Figure, the hinging of the magnetotail current sheet towards the equator in a tilted configuration results in a longer convection pathway for open field lines in the Northern hemisphere, as the reconnection site on the nightside is shifted more weakly than on the dayside. This introduces a North‐South asymmetry in magnetospheric convection, driving more FAC in the Northern ionosphere for large tilt angles than in the South independent of hemispheric differences in conductance. These results highlight the strong sensitivity to onset time in the potential impact of a severe space weather event, since the intensity of stormtime FACs at a given location on the ionosphere will depend closely on the orientation of the dipole axis.

    Animation showing the response of field configuration and current density to changing dipole tilt angle. The corresponding FACs response is also shown.

    Figure: Animation of the effect of a changing dipole tilt angle on the magnetosphere-ionosphere system. The left panel shows a contour map of the magnetospheric current density in the noon-midnight meridian plane, with magnetic field lines in black. The orange crosses mark the approximate location of the dayside and nightside reconnection sites; the white dashed line shows the magnetopause location, and the solid white line represents the magnetic equator. The two right panels show contours of the FAC in the northern and southern ionosphere, with the open-closed boundary as a black dotted line.

    Please see the paper for full details:

    Eggington, J. W. B., Eastwood, J. P., Mejnertsen, L., Desai, R. T., & Chittenden, J. P. (2020). Dipole tilt effect on magnetopause reconnection and the steady‐state magnetosphere‐ionosphere system: Global MHD simulations. Journal of Geophysical Research: Space Physics, 125, e2019JA027510. https://doi.org/10.1029/2019JA027510

    Statistics of Solar Wind Electron Breakpoint Energies Using Machine Learning Techniques

    By Mayur Bakrania (Mullard Space Science Laboratory, UCL)

    Solar wind electron velocity distributions at 1 au consist of a thermal 'core' population and two suprathermal populations: 'halo' and 'strahl'. The core and halo are quasi-isotropic, whereas the strahl typically travels along the parallel and/or anti-parallel direction with respect to the interplanetary magnetic field. The energies at which the halo and strahl populations are separated from the core population are known as the breakpoint energies, and these energies provide useful information on the relative importance of scattering mechanisms.

    With Cluster-PEACE data, we analyse energy and pitch angle distributions and use machine learning techniques to separate and classify these solar wind populations. In our statistical study, we apply the K-means algorithm to phase space density distributions over ten years to study the variation of halo and strahl breakpoint energies with solar wind parameters. Key findings include:

    • Halo and strahl suprathermal breakpoint energies increase with core temperature, with the halo exhibiting a more positive gradient than the strahl, as shown in the Figure. We conclude low energy strahl electrons are scattering into the core, instead of the halo. This increases the number of Coulomb collisions and extends the perpendicular core population to higher energies, resulting in a larger difference between halo and strahl breakpoint energies at higher core temperatures.
    • Suprathermal breakpoint energies decrease with increasing solar wind speed. We also observe distinct profiles for fast and slow solar wind and conclude the origin of the solar wind, i.e., coronal holes for fast wind or streamer belt regions for slow wind, potentially plays a role in the definition of thermal and non-thermal electron populations. 

    This extensive and novel study reveals key characteristics of the solar wind electron populations. The results provide crucial information on the generation of solar wind electron populations as the solar wind propagates through the heliosphere.

    Violin plots showing that both the halo and strahl breakpoint energies increase with core temperature.

    Figure. (Top) `Violin plot' of halo breakpoint energy against core temperature. The blue line shows the line of best fit. The white dots indicate the median of breakpoint energies and the thick black lines show the inter-quartile ranges (IQR). We plot the thin black lines to display which breakpoint energies are outliers. They span from Q3+1.5 X IQR to Q1-1.5 X IQR, where Q3 and Q1 are the upper and lower quartiles, respectively. The horizontal width of the red regions represents the density of data points at that given breakpoint energy. (Bottom) `Violin plot' of strahl breakpoint energy against core temperature. The orange line shows the line of best fit.

    Please see the paper for full details:

    Bakrania, M. R., Rae, I. J., Walsh, A. P., Verscharen, D., Smith, A. W., Bloch, T. & Watt, C. E. J. (2020). Statistics of solar wind electron breakpoint energies using machine learning techniques, A&A, 639, A46, https://doi.org/10.1051/0004-6361/202037840 

    Statistical Uncertainties of Space Plasma Properties Described by Kappa Distributions

    by Georgios Nicolaou (Mullard Space Science Laboratory, UCL)

    In-situ plasma instruments are often designed to provide the measurements we need to construct the three dimensional velocity distribution functions of plasma species. The proper analysis of the constructed velocity distribution functions derives the bulk properties of the plasma species which are essential in the investigation of the physical mechanisms in plasmas. Although state-of –the-art instruments provide high quality measurements, it is impossible to completely overcome the statistical error related to the counting statistics. The counting error introduces an error to the derived parameters, which is important to quantify in order to define the significance level of the scientific results. The authors simplify the formulas that estimate the statistical error of the plasma parameters which are derived as the statistical moments of observed distribution functions. The simplicity of these expressions allow fast on-board and on-ground calculations. The authors verify the accuracy of the simplistic expressions using numerical simulations of solar wind plasma particles with their velocities following kappa distribution functions. Moreover, the authors explore and quantify the expected error as a function of the distribution function properties.

    Plots showing the dependence of standard deviation on counting statistics.

    Figure 1. Normalized standard deviations of the derived (upper left) plasma density, (upper right) bulk speed, (lower left) temperature, and (lower right) kappa index as functions of the maximum counts Cexp, and for VDFs with the same density, speed and temperature, but four different input kappa indices; (black) κ = 2, (orange) κ = 2.5, (blue) κ = 4, and (red) κ = 8. Each data-point is the standard deviation of 1000 values determined from the moments of distribution functions constructed from simulated data.

    For more information please see:

    Nicolaou, G. & Livadiotis, G. (2020). Statistical Uncertainties of Space Plasma Properties Described by Kappa Distributions. Entropy, 22, 541. https://www.mdpi.com/1099-4300/22/5/541 

    The full paper can be found at: https://www.mdpi.com/1099-4300/22/5/541

    Quantifying the Solar Cycle Modulation of Extreme Space Weather

    By Sandra Chapman (University of Warwick)

    The daily sunspot number record available since 1818 is used to map solar activity over 18 solar cycles to a standardised 11 year cycle or ‘clock’. No two solar cycles are the same, but using the Hilbert transform we are able to standardise the solar activity cycle. The clock reveals that the transitions between quiet and active periods in solar activity are sharp. Once the clock is constructed from sunspot observations it can be used to order observations of solar activity and space weather. These include occurrence of solar flares seen in X-ray by the GOES satellites and F10.7 solar radio flux that tracks solar coronal activity. These are all drivers of space weather on the Earth, for which the longest record is the aa index based on magnetic field measurements going back over 150 years. All these observations show the same sharp switch on and switch off times of activity. Once past switch on/off times are obtained from the clock, the occurrence rate of extreme events when the sun is active or quiet can be calculated, and we find only 1-3% of extreme space storms over the last 150 years occurred in the quiet period of the solar cycle clock.

    Plot showing how different measures of activity vary over multiple solar cycles.

    Figure: Multiple cycles of the irregular, but roughly 11 year cycle of solar and geomagnetic activity is mapped onto a regular solar cycle clock with increasing time read clockwise. Circles indicate the cycle maxima (red), minima (green) and terminators (blue). Measures of solar activity are the daily F10.7 solar radio flux (blue), and GOES X-class, M-Class and C-class solar flare occurrence plotted (red, blue and green scaled histograms). Extreme space weather events at earth seen in the aa geomagnetic index are shown as black dots arranged on concentric circles where increasing radius indicates aa values which in any given day exceeded 100, 200, 300, 400, 500, 600nT, large events appear as ‘spokes’. The clock identified when activity switches on at the terminator and switches off at the pre-terminator (blue lines).

    For more information please see:

    Chapman S. C., McIntosh, S. W., Leamon, R. J., & Watkins, N. W. (2020). Quantifying the solar cycle modulation of extreme space weather. Geophysical Research Letters, 47, e2020GL087795. https://doi.org/10.1029/2020GL087795