Magnetosphere, Ionosphere and Solar-Terrestrial

Latest news

New MIST Council 2021-

There have been some recent ingoings and outgoings at MIST Council - please see below our current composition!:

  • Oliver Allanson, Exeter (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2024 -- Chair
  • Beatriz Sánchez-Cano, Leicester (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2024
  • Mathew Owens, Reading (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2023
  • Jasmine Sandhu, Northumbria (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2023 -- Vice-Chair
  • Maria-Theresia Walach, Lancaster (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2022
  • Sarah Badman, Lancaster (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2022
    (co-opted in 2021 in lieu of outgoing councillor Greg Hunt)

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/  

    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!

    Observations of closed magnetic flux embedded in the lobes during periods of northward IMF

    By Laura Fryer (University of Southampton)

    The coupling between the Interplanetary Magnetic Field (IMF) and the magnetosphere has been extensively studied over the last few decades. This has been facilitated by the launch of multiple spacecraft, such as ESA’s Cluster mission (Escoubet et al 2001), which probes different regions of the Earth's magnetosphere. There have been many studies dedicated to understanding the response of the magnetosphere during more turbulent southward orientated IMF conditions, however, there is still great uncertainty in our understanding of how the magnetosphere, particularly the magnetotail, responds to northward IMF. In general, the lobes in the Earth's magnetotail are typically described as having cool, low energy and often low density plasma populations and therefore hot plasma observations are unexpected in these regions of the magnetosphere. Despite this, there have been a small number of studies reporting energetic plasma populations in the lobes during northward IMF conditions (Huang et al 1987, Shi et al 2013, Fear et al 2014).

    We present three case studies which show hot plasma embedded in the lobes of the magnetosphere. For two of these case studies, simultaneous observations of the plasma sheet confirmed that the energies observed within the lobe were directly comparable in magnitude to the populations in the plasma sheet. In addition to this, we observed plasma characteristics which indicated that the plasma is likely to be on closed field lines (evidenced by electron pitch angle distributions and variation in motion of the spacecraft). Tracing the footprint of these field lines to ionospheric altitudes revealed that in each Event, the footprint intersected with a transpolar arc. An example of this for Event 2 can be seen in Figure 1, which shows the footprint of each of the Cluster spacecraft in the tetrahedron, intersecting with a transpolar arc. This provided further evidence to suggest that the energetic plasma was likely to form on closed field lines and could be explained well by the result of recent magnetotail reconnection during northward IMF conditions, a mechanism proposed by Milan et al 2005 to explain the formation of transpolar arcs.

    A multipanel plot showing auroral images at different time steps. Overplotted on the auroral image are the spacecraft footprints. 

    Figure 1: SSUSI (DMSP-F16) FUV auroral observations from the Northern Hemisphere. The panels show the images taken from 16:06 UT to 19:28 UT for Event 2. The data is plotted in AACGM coordinates (magnetic latitude, MLT). The top three images are repeated in the bot-tom row but overplotted with the footprints of Cluster 1, 2, 3 and 4. This has been traced using the T96 model (Tsyganenko, 1996) to an altitude of 120km and are represented by black, red, green and blue circles respectively.

    Please see the paper for full details:

    Fryer, L. J., Fear, R. C., Coxon, J. C., & Gingell, I. L. (2021). Observations of closed magnetic flux embedded in the lobes during periods of northward IMF. Journal of Geophysical Research: Space Physics, 126, e2021JA029281. https://doi.org/10.1029/2021JA029281 

    Average Ionospheric Electric Field Morphologies During Geomagnetic Storm Phases

    By Maria-Theresia Walach (Lancaster University)

    Geomagnetic storms are a global electrodynamic phenomenon, during which the ring current is loaded with energy. The coupled magnetospheric/ionospheric system responds during a geomagnetic storm and the dynamics of the system can be monitored using measurements of the high-latitude ionosphere. Ordering data from the Super Dual Auroral Radar Network (SuperDARN) by geomagnetic storm phase, we produce convection maps for a geomagnetic storm, which allow us to discern changes that occur in association with the development of the storm phases. We utilize principal component analysis to identify and quantify the primary electric potential morphologies during geomagnetic storms. Along with information on the size of the patterns, the first six eigenvectors provide over ∼80% of the variability in the morphology, providing us with a robust analysis tool to quantify the main changes in the patterns. Studying the first six eigenvectors and their eigenvalues shows that the primary changes in the morphologies with respect to storm phase are the convection potential enhancing and the dayside throat rotating from pointing toward the early afternoon sector to being more sunward aligned during the main phase of the storm. We find that the ionospheric electric potential increases through the main phase and then decreases once the recovery phase begins. Furthermore, we find that a two‐cell convection pattern is dominant throughout and that the dusk cell is overall stronger than the dawn cell.

    The figure shows the mean electrostatic potential, followed by the first six eigenvectors. These show the most common components that can be used to make up the ionospheric convection patterns during geomagnetic storms.

     Multipanel plot showing the first six components and mean electrostatic potential

    Figure Caption: Ionospheric electric field component patterns showing the mean for geomagnetic storms (top left), followed by the patterns corresponding to the first six eigenvectors of the Principal Component Analysis. Each pattern is centered on the geomagnetic pole, with 12:00 magnetic local time pointing toward the top of the page, and dusk toward the left. Lines of geomagnetic latitudes are indicated from 40° to 90° by the dashed gray circles.

    Animation showing convection patterns from SuperDARN data for geomagnetic storm main phase

    Animation Caption: Average convection patterns from SuperDARN data for geomagnetic storm main phase

    Please see the paper for full details: Walach, M.‐T.,  Grocott, A., &  Milan, S. E. (2021).  Average ionospheric electric field morphologies during geomagnetic storm phases. Journal of Geophysical Research: Space Physics,  126, e2020JA028512. https://doi.org/10.1029/2020JA028512

    Network community structure of substorms using SuperMAG magnetometers

    By Lauren Orr (University of Warwick)

    Geomagnetic substorms are a global magnetospheric reconfiguration, during which energy is abruptly transported to the ionosphere. Central to this are the auroral electrojets, large-scale ionospheric currents that are part of a larger three-dimensional system, the substorm current wedge. Many, often conflicting, magnetospheric reconfiguration scenarios have been proposed to describe the substorm current wedge evolution and structure. We have used well-established network science techniques to analyze data from >100 ground-based magnetometers operated by the SuperMAG collaboration1.  We translated this data into a time-varying directed network, based on canonical cross-correlation of the vector magnetic field perturbations measured at each magnetometer pair2,3 and performed community detection on the network4. Communities are locally dense but globally sparse groups of connections in the network, identifying emerging coherent patterns in the current system as the substorm evolves. Analysis of 41 substorms exhibit robust structural change from many small, uncorrelated current systems before substorm onset, to a large spatially-extended coherent system, between 10-20 minutes after onset. We interpret this as strong indication that the auroral electrojet system during substorm expansions is inherently a large-scale phenomenon and is not solely due to many meso-scale wedgelets.

    Panels showing the evolution of the community structure during substorms. The top panels show temporal variations in the communities and connections. Panels on the bottom show snapshots at times of interest.

    Figure 1: The community structure of a substorm on the 16/03/1997. The abscissa of all panels is normalized time, where t'=0 is onset (dashed green line) and t'=30 (dashed purple line) is the time of maximum auroral bulge expansion. Panels 1-2 plots individual communities as circles where the size of the circle reflects the  number of connections within the community. The ordinate plots the mean MLT/MLAT of the community, and the color indicates the proportion of connections with each time lag, |τc|. The dashed lines overplotted are the edges of the auroral bulge (MLT) and the onset location (MLAT), found from auroral images. Panel 3 shows snapshots of the community structure at time points t’=0 (onset), t’=10 and t’=20, overplotted on maps provided by SuperMAG1. There is a clear shift from many, small uncorrelated communities before onset to one large correlated system half way through the expansion phase.

    Please see the paper for full details:

    Orr, L., Chapman, S.C., Gjerloev, J.W. et al. Network community structure of substorms using SuperMAG magnetometers. Nat Commun 12, 1842 (2021). https://doi.org/10.1038/s41467-021-22112-4

    The Cushion Region and Dayside Magnetodisc Structure at Saturn

    By Ned Staniland (Imperial College London)

    The moons Enceladus and Io are internal plasma sources for the magnetospheres of Saturn and Jupiter, respectively. This, coupled with their rapid rotation rates (~10 h), radially stretches the magnetic field from a dipole to a magnetodisc. However, this structure can break down at large distances where the magnetic field can no longer contain the equatorial plasma. This quasi-dipolar layer between the current sheet outer edge and magnetopause is known as the “cushion region.” This has previously been observed at Jupiter, predominantly at dawn, but not at Saturn (Went et al., 2011). It is suggested to be populated by mass-depleted flux tubes following magnetotail reconnection.

    We present the first evidence of a cushion region forming at Saturn. From the complete Cassini orbital dataset, only five examples are identified, showing this phenomenon to be rare, with four at local time dusk and one pre‐noon. The dusk cushion observed could be due to asymmetric heating of plasma in the Saturn system (Kaminker et al., 2017), as well as the changing magnetic field configuration through dusk where the field is less confined by the magnetopause, resulting in disc instabilities (Kivelson and Southwood, 2005).

    These results highlight a key difference between the rotationally driven magnetospheres of Saturn and Jupiter. The rare cushion region examples found and evidence of patchy reconnection at Saturn (Delamere et al., 2015) compared to the persistent cushion region at Jupiter (Went et al., 2011) and statistical x-line across the Jovian tail (Vogt et al., 2010) shows that the mass transport and loss mechanisms differ between these systems. Whilst the Saturn system is often described as being between Jupiter and the Earth in terms of dynamics and structure, these results suggest that this is perhaps an oversimplified description.

    An example of a cushion region is shown on the left, where the magnetic field observations indicate a transition from magnetodisc-like to quasi-dipolar. A schematic is included on the right where regions are colour-coded to indicate the expected locations of disc-like and dipolar-like fields.

    Figure: The left plot shows an example of a cushion region at Saturn. The top panel shows magnetic field data. The second panel showing the relative contributions of the radial (green) and meridional (blue) components to the total field. The third panel shows the angle between the observed field and a dipole. For this example, the field is disc-like in the middle magnetosphere, but the structure breaks down in the outer magnetosphere (highlighted by the background colours). The right plot shows the average dayside magnetic field configuration. The field is more disc-like in the dawn sector whilst there is a quasi-dipolar region in the outer magnetosphere at dusk.

    Please see the full paper for details:

    Staniland, N. R., Dougherty, M. K., Masters, A., & Achilleos, N. (2021). The cushion region and dayside magnetodisc structure at Saturn. Geophysical Research Letters, 48, e2020GL091796. https://doi.org/10.1029/2020GL091796

    Particle-In-Cell Simulations of the Cassini Spacecraft's Interaction with Saturn's Ionosphere during the Grand Finale

    By Zeqi Zhang (Imperial College London)

    Cassini's Grand Finale at Saturn was the first time the giant planet’s atmosphere had been sampled in-situ. The ionosphere, and indeed the Saturn system as a whole, provided a uniquely different environment compared to the terrestrial planets and also Jupiter, with populations of charged dust grains influencing the plasma dynamics.  When passing through Saturn’s ionosphere, Cassini observed an ionosphere dominated by ice and dust particles which continually rain inward from Saturn’s vast ring system and soak up free electrons, thus producing a dusty complex plasma.  Understanding how incident plasma currents charge a spacecraft relative to its surrounding environment is important for interpreting the surrounding plasma conditions and on-board plasma measurements.  In this article, we describe three dimensional Particle-In-Cell simulations of the Cassini spacecraft’s interaction with plasmas representative of Saturn's ionosphere during the Grand Finale.

    The global simulations revealed complex interaction features such as a highly structured wake containing spacecraft-scale vortices and electron wings, a Langmuir wave analogue of Alfvén wings, which propagated at small angles to the magnetic field and upstream into the pristine plasma ahead of Cassini. The results explain how a large negatively charged plasma component combined with a large negative to positive ion mass ratio is able to drive the spacecraft to the observed positive potentials, a previously unexplained phenomenon observed during end-of-mission.  Despite the high electron depletions, the electron properties are found as a significant controlling factor for the spacecraft potential together with the magnetic field orientation which induces a potential gradient directed across Cassini's asymmetric body. This study reveals the global spacecraft interaction experienced by Cassini during the Grand Finale in a plasma environment dominated by a class of physics quite different to those considered in the classical view of spacecraft charging.

    Figure shows a schematic of the Cassini spacecraft configuration in the simulation. Bottom panels show the electron, ion, and negative ion density spatial distributions.

    Figure 1. The upper schematic shows the simulation configuration for Cassini during Grand Finale Rev 292 ingress at 2500 km Saturn altitude. The lower panels shows the electron (left-hand panel), ion (centre panel) and negative ion (right-hand panel) densities in the Y-Z plane through Cassini’s main body. The plasma wake is longer for the larger species and electron wing structures are visible in the electron density which propagate at small angles to the ambient magnetic field.

    Please see the paper for full details:

    Zhang, Z., Desai, R.T., Miyake, Y., Usui, H., Shebanits, O., (2021). Particle-In-Cell Simulations of the Cassini Spacecraft’s Interaction with Saturn’s Ionosphere during the Grand Finale. Monthly Notices of the Royal Astronomical Society, Volume 504, Issue 1, pp 964 - 973, https://doi.org/10.1093/mnras/stab750.