MIST

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!

    Distributions of Birkeland current density observed by AMPERE are heavy‐tailed or long‐tailed

    Distributions of Birkeland current density observed by AMPERE are heavy‐tailed or long‐tailed

    By John Coxon (Northumbria University)

    Electric currents flow above Earth’s surface in the ionosphere; along the magnetopause; across the magnetotail; and in the same region of space as the radiation belts. These currents are all closed through currents flowing along the magnetic field lines in near-Earth space forming one large current circuit; the currents flowing along the field lines are known as field-aligned currents, or as Birkeland currents.

    Birkeland currents are, therefore, the currents that communicate impacts from the solar wind (at the magnetopause) and from phenomena such as substorms (in the magnetotail) into the ionosphere, and a key part of the puzzle in understanding phenomena such as ground-based magnetic perturbations such as GICs.

    In this paper, we analyse the distributions of the Birkeland current densities measured by a dataset called AMPERE. We find that the distributions are heavy-tailed, which means that they are more likely to display extreme behaviours than if they were distributed normally. We determine that the best model to describe the distributions is a q-exponential model, and we exploit this to find the probability of currents flowing above some given threshold.

    We can use this to make maps of the probability of extreme current flows in the Northern and Southern Hemispheres (Figure 1). We can see that the most extreme currents are most likely to be on the dayside of Earth, and at a magnetic colatitude of ~20° (a latitude of ~70°), and we can see that extreme currents are much more likely in the Northern Hemisphere. This has important ramifications for space weather prediction, but also for the physical drivers of the currents; more details are available in the full paper.
    A graph showing the probability of extreme current on four maps which are for positive and negative currents in the Northern and Southern Hemispheres. The strongest currents are at 20° magnetic colatitude in the Northern Hemisphere.
    Figure 1: Maps of the probability P that the magnitude of current density |J| ≥ 4.0 µA m−2 in the years 2010–2012. P is presented for positive current densities (left column) and negative current densities (right column) in the Northern Hemisphere (top row) and Southern Hemisphere (bottom row). Bins in which the probability could not be computed were set to zero.
    Please see paper for full details: Coxon, J. C., Chisham, G., Freeman, M. P., Anderson, B. J. & Fear, R. C. Distributions of Birkeland current density observed by AMPERE are heavy‐tailed or long‐tailed. _J Geophys Res Space Phys_ (2022) https://doi.org/10.1029/2021ja029801.

     

    Acceleration of Electrons by Whistler-Mode Hiss Waves at Saturn

    By Emma Woodfield (British Antarctic Survey)

    Whistler-mode hiss waves are well known for causing losses of energetic electrons from the radiation belts at the Earth through wave-particle interactions. The result of the interactions of charged particle with plasma waves, whether energy is transferred from wave to particle or vice-versa, is dependent on many factors including the background plasma conditions. In Saturn’s magnetosphere there is a torus of charged particles, the primary source of this plasma torus is neutral water particles emitted from the moon Enceladus which are then ionised. The combination of pressure, ambipolar electric field, centrifugal and gravitational forces on this moon sourced plasma creates a regime where density is highest near the magnetic equator and notably lower at higher latitudes. Consequently, the ratio of plasma frequency to electron gyrofrequency frequently falls below one at higher latitudes. This also coincides with the region where hiss mode waves are observed and our simulations show that this very low ratio leads hiss waves at Saturn to accelerate electrons rather than scattering them out of the radiation belt. This new finding has important implications for the radiation belt dynamics at Saturn since hiss waves are strong and frequently observed.

     

    Another result of the high latitude occurrence of hiss (> 25 degrees) is that only electrons which bounce a good distance along the magnetic field lines will encounter these particular wave-particle interactions. Therefore, the energy increase in the electrons due to the hiss waves is only seen in these particles. We can describe how far along the magnetic field a particle will reach using the equatorial pitch angle, which is the angle between the particle velocity and the magnetic field at the magnetic equator. An electron with an equatorial pitch angle of 90 degrees is confined to the equator whereas one of 0 or 180 degrees will reach all the way down to the planet in different hemispheres. The result of the hiss wave interactions is to drive the pitch angle distributions of the electrons towards a “butterfly shape” with peaks at low (and very high) equatorial pitch angle reflecting the hiss interactions at high latitudes in both hemispheres. The strength and speed of the interaction also varies with electron energy, the figure shows how our simulations of the electron pitch angle distributions at different L-shells (radial distance along the magnetic equator of a magnetic field line) progress after one Earth day for three typical radiation belt energies. These simulations consider only the effect of the hiss waves to isolate their effect from radial diffusion and transport and any other wave-particle interactions or collisional losses. Highly anisotropic pitch angle distributions (with the peak at lowest and highest pitch angle) are apparent in all three energies in even this relatively short timescale simulation.

    Equatorial pitch angle distributions from 2D model runs at a given L-shell after 24 hours with a resolution of 0.1L. Each run considers the energy and pitch angle diffusion, no radial diffusion or radial transport is included. Each pitch angle distribution is normalised to the flux value at 90 degrees. (a) initial condition for all energies, (b,c,d) flux at 0.4, 1.0 and 3.0 MeV respectively.         From: Emma Woodfield - BAS  Sent: 27 January 2022 13:50 To: Walach, Maria <m.walach@lancaster.ac.uk> Subject: RE: [External] MIST Nugget   Hi Maria,   Will do 😊   There’s a BAS news twitter – I’ll double check the twitter handle.   Thanks Emma   From: Walach, Maria <m.walach@lancaster.ac.uk>  Sent: 27 January 2022 12:36 To: Emma Woodfield - BAS <emmwoo@bas.ac.uk> Subject: Re: [External] MIST Nugget   Hi Emma,   Great!   Could you prepare one within the next 1-2 weeks?    I also advertise new nuggets via the MIST twitter page. Please let me know if you have any twitter account(s) that you would like me to tag in the post or any suggested wordings.   Thanks, Maria   On 27 Jan 2022, at 12:29, Emma Woodfield - BAS <emmwoo@bas.ac.uk> wrote:   This email originated outside the University. Check before clicking links or attachments. Hi Maria,   That was a quick spot – I haven’t even checked the online version myself yet! :-)     Yes happy to do a nugget, when would you like it by?   Kind regards Emma   From: Walach, Maria <m.walach@lancaster.ac.uk>  Sent: 27 January 2022 12:28 To: Emma Woodfield - BAS <emmwoo@bas.ac.uk> Subject: MIST Nugget   Hi Emma,   I hope all is well with you!   I am contacting you on MIST Council business, due to your recent article (https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2021GL096213?campaign=wolacceptedarticle). MIST nuggets are short, 1-2 paragraphs (100 - 300 words) accompanied by a figure/animation that describes the importance and some key result/aspect of your work, as well as a caption for the figure and any references.. For some examples please see http://www.mist.ac.uk/nuggets. They are aimed to be understandable for the general MIST audience - at the level of a 1st year PhD student, with a focus on clear language and the wider impact of the results.   We would like to invite you to contribute to the series of MIST nuggets and provide a short nugget on your recently published work. Hopefully this should not take much time to write, and it is a great way to advertise your work to the wider MIST community! Please would you be able to let me know whether or not you will be able to contribute at your earliest convenience.   Many thanks,    Maria On behalf of MIST council -------------------------------------------------- Maria-Theresia Walach Senior Research Associate Space and Planetary Physics Group Physics Department Lancaster University Lancaster LA1 4YB UK   This email and any attachments are intended solely for the use of the named recipients. If you are not the intended recipient you must not use, disclose, copy or distribute this email or any of its attachments and should notify the sender immediately and delete this email from your system. UK Research and Innovation (UKRI) has taken every reasonable precaution to minimise risk of this email or any attachments containing viruses or malware but the recipient should carry out its own virus and malware checks before opening the attachments. UKRI does not accept any liability for any losses or damages which the recipient may sustain due to presence of any viruses.   

    Figure Caption: Equatorial pitch angle distributions from 2D model runs at a given L-shell after 24 hours with a resolution of 0.1L. Each run considers the energy and pitch angle diffusion, no radial diffusion or radial transport is included. Each pitch angle distribution is normalised to the flux value at 90 degrees. (a) initial condition for all energies, (b,c,d) flux at 0.4, 1.0 and 3.0 MeV respectively.

     

    See full paper for details:

    Woodfield, E. E., Glauert, S. A., Menietti, J. D., Horne, R. B., Kavanagh, A. J., & Shprits, Y. Y. (2022). Acceleration of electrons by whistler-mode hiss waves at Saturn. Geophysical Research Letters, 49, e2021GL096213. https://doi.org/10.1029/2021GL096213

    Publication URL: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021GL096213

     

    Weak Turbulence and Quasilinear Diffusion for Relativistic Wave-Particle Interactions Via a Markov Approach

    By Oliver Allanson (Exeter University)

    Quasilinear diffusion theory forms the basis of much of the modelling and interpretation of particle transport and energization due to interactions with electromagnetic waves; at terrestrial and planetary radiation belts; in the solar atmosphere and solar wind; and for the dynamics of cosmic rays.

    We present a derivation of weak turbulence and quasilinear diffusion theories in energy and pitch-angle space that differs from the most standard methods of derivation (based upon the Vlasov equation [1]). We

    1. start from solutions to the single-particle Lorentz force equation
    2. expand the relevant equations of motion up to second order in a small parameter (magnitude of magnetic perturbations to background field)
    3. ensemble average the solutions to obtain the diffusion coefficients.

    The approach used in this paper builds upon the work by [2], in which only pitch-angle dynamics were considered.

    The main conclusions and results of this paper are as follows:

    1. A derivation and discussion of the general Fokker-Planck equation to describe stochastic charged particle dynamics. This equation includes all possible advective and diffusive dynamics, in principle. The form of the drift and diffusion coefficients are then to be determined on a system-by-system basis. We solve for the diffusive dynamics only, and leave investigations of the drift coefficients and drift-diffusion relations for future works
    2. The weak turbulence diffusion coefficients: i) display an interesting dependency on time (see Figure1); ii) and also explicitly incorporate the effects of non-resonant particles, as well as the standard effects of cyclotron-resonant particles
    3. We recover the standard form as used in the resonant-diffusion limit of relativistic quasilinear theory [3], when we consider elapsed timescales much greater than a gyroperiod
    4. Our new derivation has a number of benefits, including: 1) the relationship between a more general weak turbulence theory and the standard resonant diffusion quasilinear; 2) the general nature of the Fokker-Planck equation that can be derived without any prior assumptions regarding its form; 3) the clear dependence of the form of the Fokker-Planck equation and the transport coefficients on given specific timescales.

    Figure showing time-dependency is relevant for diffusion.

     See paper for full details: Allanson O, Elsden T, Watt C and Neukirch T (2022) Weak Turbulence and Quasilinear Diffusion for Relativistic Wave-Particle Interactions Via a Markov Approach.  Front. Astron. Space Sci. 8:805699. doi: 10.3389/fspas.2021.805699 

     

    1: C. F. Kennel and F. Engelmann , "Velocity Space Diffusion from Weak Plasma Turbulence in a Magnetic Field", The Physics of Fluids 9, 2377-2388 (1966)

    2: Don S. Lemons , "Pitch angle scattering of relativistic electrons from stationary magnetic waves: Continuous Markov process and quasilinear theory", Physics of Plasmas 19, 012306 (2012)

    3: Glauert, S. A., and Horne, R. B. (2005), Calculation of pitch angle and energy diffusion coefficients with the PADIE code, J. Geophys. Res., 110, A04206

     

    Magnetopause ripples going against the flow form azimuthally stationary surface waves

    By Martin Archer (Imperial College London)

    Like waves on water, surface waves on the outer boundary of Earth’s magnetosphere, the magnetopause are thought to always travel in the direction of the driving solar wind. Indeed, many observations of the global dynamics of the magnetosphere show that disturbances travel tailward, i.e. with the wind, for both steady and impulsive driving. However, we find that the lowest-frequency magnetopause surface waves, which form standing waves along the terrestrial magnetic field, actually propagate against the flow outside the boundary.

    Multi-spacecraft observations of the resonant surface waves excited by an isolated magnetosheath jet show that the speed of the waves’ energy flow is comparable, but in opposition, to the magnetosheath velocity. Global MHD simulations of the magnetospheric response to a pressure pulse reveal the inward/outward boundary motion is azimuthally stationary across a wide local time range (09-15h). This is despite significant flows being present that should otherwise advect the waves tailward. We show in the figure this is possible since the surface waves’ Poynting flux (panel a) exactly balances the flow's advective effect (panel b) leading to no net energy flux (panel c) over this local time range. Further down the equatorial flanks, however, advection dominates hence the waves travel downtail, seeding fluctuations at the resonant frequency which subsequently grow in amplitude via the Kelvin-Helmholtz instability. Our findings are also in excellent agreement with simple analytic theory. We, therefore, illustrate our overall conclusions in the right panel of the figure.

    These unexpected results reveal that magnetopause surface waves can persist longer than was previously expected, which will have implications upon radiation belt, ionospheric, and auroral dynamics. Furthermore, since surface waves drive dynamics in many space, astrophysical and laboratory plasma systems, the results made possible by in situ measurements, may have applications to other environments where these are not possible, for example coronal loops.

    Figure showing surface wave energy fluxes tangential to the magnetopause.
    Figure: Surface wave energy fluxes tangential to the magnetopause. Panels show the Poynting (a) and advective (b) energy fluxes tangential to the magnetopause along magnetopause normals. Integrals along the normal are shown in panel c for the Poynting (purple) and advective (green) fluxes along with their sum (black). On the right an animation of the global dynamics is shown (credit Martin Archer / Emmanuel Masongsong / NASA).

    Please see paper for full details: Archer, M.O., Hartinger, M.D., Plaschke, F. et al. Magnetopause ripples going against the flow form azimuthally stationary surface waves. Nat Commun 12, 5697 (2021). https://doi.org/10.1038/s41467-021-25923-7

    The Roles of the Magnetopause and Plasmapause in Storm-Time ULF Wave Power Enhancements

    By Jasmine Kaur Sandhu (Northumbria University)

    The Earth’s magnetosphere experiences extreme and dramatic changes during geomagnetic storms due to strongly enhanced solar wind conditions. One impact of the elevated solar wind conditions is the increased occurrence and amplitude of Ultra Low Frequency (ULF) waves across the dayside magnetosphere. These ULF waves are of particular interest due to their implications for transporting and coupling energy within the magnetosphere. However, the radial distribution of ULF wave power is complex – controlled interdependently by external solar wind driving and the internal magnetospheric structuring.

    In this study, we explored how ULF wave power is distributed radially in the dayside magnetosphere. We conducted a statistical analysis of storm-time ULF wave power observations from the Van Allen Probes. The results showed that accounting for the plasmapause and (especially) the magnetopause locations reduce statistical variability and improve parameterisation of spatial trends over and above using the L value, highlighting the importance of these boundaries in controlling where and when enhanced ULF wave power is present.

    A key finding was the importance of local plasma density. We find that during geomagnetic storms, high density patches in the afternoon sector (e.g. plasmaspheric plumes) act to “trap” ULF waves, leading to spatially localised patches of very high ULF wave power. Figure 1 shows one example of high ULF wave power confined within a patch of enhanced density. The results have critical implications for understanding how ULF waves propagate within the terrestrial magnetosphere, and highlights the importance of the highly distorted storm-time cold plasma density distribution on wider geomagnetic processes.

    A multi-panel plot showing time series of Van Allen Probes observations during an event.

    Figure 1. Timeseries for 27 August 2015 showing the (a) Sym-H index [nT], (b) Earthward component of the solar wind speed, |vX| [km s-1], and (c) Southward IMF component, BZ [nT]. Panels (d-i) show time series for the Van Allen Probes A (pink) and B (blue). We show (d) L value and (e) MLT [h] of the spacecraft location, and (f) total electron density, ne [cm-3]. Panels (g) and (h) show power, P(f) [nT2 Hz-1], as a function of frequency, f [mHz], and time for Probe A and Probe B, respectively. Panel (i) shows the power, P [nT2 Hz-1], summed over the ULF wave band.

    Please see the paper for full details:

    Sandhu, J. K., Rae, I. J., Staples, F. A., Hartley, D. P., Walach, M.-T., Elsden, T., & Murphy, K. R. (2021). The Roles of the Magnetopause and Plasmapause in Storm-Time ULF Wave Power Enhancements. Journal of Geophysical Research: Space Physics, 126, e2021JA029337. https://doi.org/10.1029/2021JA029337