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!

    Tomographic imaging of travelling ionospheric disturbances

    By Karl Bolmgren (University of Bath)

    The ionosphere, the electrically charged upper atmosphere, has important effects on technologies like radio communication and satellite-based positioning. For high-accuracy positioning using Global Navigational Satellite Systems (GNSS), such as the Global Positioning System (GPS), ionospheric models are often used to estimate the ionospheric effect on satellite to ground communication. This effect is determined by the ionospheric electron content, and sudden changes or disturbances in the electron content can be challenging to include in such models.

    A common type of disturbance called Travelling Ionospheric Disturbances (TIDs) are caused by gravity waves in the ionosphere, which are present all over the globe. They can be observed as wave-like fluctuations in Total Electron Content (TEC) and come in widely different spatial and temporal scales. The largest TIDs are generally caused by geomagnetic storm activity, while the more common, smaller TIDs can be caused by activity in the neutral atmosphere, like thunderstorms, perturbations from earthquakes or tsunamis, and the sudden temperature gradients associated with the solar terminator. In order to improve existing models and learn more about TIDs, we need reliable methods to study them.

    A simulated Travelling Ionospheric Disturbance

    Figure: Cross-section electron density of a modelled TID used to evaluate the tomographic images. For this particular simulation, a horizontal wavelength of 700 km, an initial perturbation speed of 20 m/s, and a period of 30 min was used.

    Computerised ionospheric tomography is a powerful tool to image the ionosphere. Tomography is a technique used to reconstruct the 3D structure of an object from integrated measurements and is commonly used in e.g. medical imaging. In ionospheric tomography, the 3D ionospheric electron density is reconstructed from integrated measurements of TEC. We have used simulated TIDs to test how well ionospheric tomography can be used to image different scales of TIDs, and an example of a simulated TID is shown in the figure. We showed that incorporating geostationary satellites can significantly improve the imaging of TIDs. The imaging technique has significant implications for how we observe and investigate ionospheric features, such as TIDs, and presents a method to incorporate these phenomena into existing ionospheric delay correction techniques for applications like GNSS.

    For more in details, please see:

    Bolmgren, K., Mitchell, C., Bruno, J., & Bust, G. (2020). Tomographic imaging of traveling ionospheric disturbances using GNSS and geostationary satellite observations. Journal of Geophysical Research: Space Physics, 125, e2019JA027551. https://doi.org/10.1029/2019JA027551  

    Local Time Asymmetries in Jupiter's Magnetodisc Currents

    By Chris Lorch (Lancaster University)

    Jupiter’s large, rapidly rotating magnetosphere is highly influenced by the presence of a global, centrifugally confined current disk comprised of co-rotating plasma from the volcanic moon Io. Azimuthal and radial currents flow through this current disk closing via magnetic field aligned currents (FACs), which are associated with Jupiter’s main auroral emission. These currents arise from dynamical processes within the magnetosphere, driven by the transport and circulation of Iogenic plasma. Characterising the structure and asymmetries in this current system is key to deciphering the dominant drivers of Jupiter’s magnetosphere-ionosphere (MI) coupled system and the behaviour of its plasma disk. 

    Previous work by Khurana [2001] examined the solar wind influence on Jupiter’s magnetosphere using equatorial maps of Jupiter’s current disk and the results demonstrated clear azimuthal asymmetries fixed with local time (LT). However, the analysis was limited the lack of spacecraft coverage in the dusk – dayside magnetosphere provided by the Galileo spacecraft.  

    Maps of current density mapped to Jupiter's equatorial plane, illustrating the azimuthal asymmetries.

    Figure 1: Equatorial maps detailing the structure of Jupiter’s current disk with Jupiter located at (0,0). Dashed circles and radial lines represent 20RJ and 1 hr local time boundaries respectively. A compressed bow shock and magnetopause (Joy et al [2002]) are shown as black solid lines. a) The radial height-integrated current density, warmer (cooler) colours are indicative of current flowing radially outwards (inwards). b) The azimuthal height integrated colour density, flowing in the direction of corotation. c) The divergence of the perpendicular height-integrated current density, indicating the location of upward and downward FACs. Warmer (cooler) colours indicate the presence of upward (downward) FACs.

    Lorch et al. [2020] determines the structure of the current disk at all LTs by considering magnetometer data at Jupiter from every available spacecraft, including Juno, up to 28 July 2018.  We apply an automated identification tool to magnetometer data from Jupiter’s current disk in conjunction with updated models of Jupiter’s intrinsic magnetic field and current disk geometry. In total, we identify 7382 lobe traversals, calculating the associated height-integrated current density for each crossing.  Additional coverage provided by the later half of the Galileo mission and the recent Juno mission allowed us to map all LTs. Asymmetries exist in both the radial (Figure 1a) and azimuthal (Figure 1b) currents into 20 RJ. Furthermore, we quantify the structure of upward and downward FACs in previously unmapped regions of Jupiter’s magnetosphere (Figure 1c). We find a positive net current density of 1.87 MA / RJ2, suggesting unmapped currents must close either down-tail or along the magnetopause. Our results demonstrate important asymmetries in Jupiter’s current systems that play a crucial role in the MI coupled system. Amalgamating these results into future MI coupling models has the potential to remove discrepancies between model predictions and observations.

    For more information, please see the paper:

    Lorch, C. T. S., Ray, L. C., Arridge, C. S., Khurana, K. K., Martin, C. J., & Bader, A. (2020). Local time asymmetries in Jupiter's magnetodisc currents. Journal of Geophysical Research: Space Physics, 125, e2019JA027455. https://doi.org/10.1029/2019JA027455 

    Where does slow Alfvénic solar wind come from?

    By David Stansby (MSSL, UCL) 

    The solar wind is a continuous flow of plasma from the surface of the Sun, flowing out into interplanetary space. Faster solar wind is known to originate in large coronal holes, but slower solar wind has a wide range of different sources. A subset of slow solar wind is filled with pure Alfvén waves, much like the fast solar wind, suggesting it has a similar origin in coronal holes.

    In our study we tested this theory of coronal hole origin, using Helios in-situ measurements of the solar wind at 0.35 AU. Figure 1 shows a wide range of plasma properties in typical fast solar wind (black), highly Alfvénic slow solar wind (blue), and non-Alfvénic slow wind (red).

    Distributions for different solar wind types are compared for proton radial velocity, alpha abundance, proton number density flux, and temperature.Distributions for different solar wind types are compared for proton radial velocity, alpha abundance, proton number density flux, and temperature.

    Figure 1: In-situ solar wind properties for three intervals of solar wind, measured at 0.35 AU. The three types of solar wind are Fast (black), Slow Alfvénic (blue), and Slow non-Alfvénic (red).

    The fast and Alfvénic slow wind had similar

    • Alpha particle abundances
    • Alpha particle drift speeds
    • Alpha particle temperature anisotropies
    • Alpha to proton temperature ratios (in both parallel and perpendicular directions) 

    These similarities imply that the heating and acceleration mechanisms of fast and slow Alfvénic solar wind are qualitatively similar, acting in the same way on protons and alpha particles. This agrees with the theory that slow Alfvénic wind originates in coronal holes, like fast solar wind.

    In contrast, the fast and Alfvénic slow wind had different

    • Electron, proton, and alpha particle temperatures
    • Mass fluxes

    These differences can be explained by different magnetic field geometries in the low corona: slower wind is released on magnetic field lines which undergo more expansion in the corona, increasing the mass flux and reducing the temperatures. This implies that whilst slow Alfvénic wind originates in coronal holes, it most probably originates in small coronal holes.

    For more information, please see:

    The origin of slow Alfvénic solar wind at solar minimum, Monthly Notices of the Royal Astronomical Society 492, 39–44 (2020), D Stansby, L Matteini, T S Horbury, D Perrone, R D’Amicis, L Berčič, https://doi.org/10.1093/mnras/stz3422

    Bifurcated Region 2 Field-Aligned Currents Associated With Substorms

    By Harneet Sangha (University of Leicester)

    The Earth’s field-aligned currents (FACs) are a key component of the solar wind-magnetosphere-ionosphere-atmosphere coupled system. They connect the magnetosphere to the ionosphere, forming two concentric rings of opposite polarity currents at dawn and dusk. The inner ring (Region 1, R1), at higher latitudes, connects to the magnetopause, whereas the lower latitude ring (Region 2, R2) connects to the inner magnetosphere. By studying them, we are able to observe the energy transfer throughout the system. They are highly variable, and the small scale changes can be difficult to detect. With the use of the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) (comprising 66-satellites that gather the data), we can observe these small scale, structures and variations in the FACs on short time scales.

    In our work, we have observed a new phenomenon which we describe as the bifurcation of the R2 currents, and the formation of a new R2 current ring (seen in Figure 1). These current signatures appear to be associated with the substorm expansion phase, and during ongoing geomagnetic activity they appear to have a 1 hour quasi-periodicity. We suggest that these bifurcations are related fast, westward flows in the midlatitude ionosphere, known as subauroral polarization streams (SAPS).

    We have proposed a new mechanism that describes the formation of these current bifurcations - consecutive particle injections into the inner magnetosphere during disturbed conditions cause separate partial ring currents to form, leading to the presence of distinct R2 current systems.

    AMPERE current density data.

    Figure 1: A series of polar projections of the AMPERE current density data for the Northern Hemisphere on 2 June 2011, from 06:50 to 08:12 UT. The colour scale for downward (blue) and upward (red) FACs saturate at ± 0.5 µA/m2. Concentric circles show colatitudes in steps of 10°, and 12 MLT (local noon) is presented at the top of the plots, with 06 MLT (dawn) on the right. The dashed box shows the dawn-dusk axis. At 06:50 UT a standard R1/R2 FAC distribution is evident. The locations of interest are highlighted in the first panel with arrows, where by 07:44 UT the R2 FACs bifurcate to form two concentric rings and can be seen between 20° and 30° colatitude.

    For more information, please see the paper:

    Sangha, H., Milan, S. E., Carter, J. A., Fogg, A. R., Anderson, B. J., Korth, H., & Paxton, L. J. (2020). Bifurcated Region 2 field‐aligned currents associated with substorms. Journal of Geophysical Research: Space Physics, 125, e2019JA027041. https://doi.org/10.1029/2019JA027041

    Evaluating the Accuracy of Solar Orbiter Plasma Measurements

    By Georgios Nicolaou (MSSL, UCL)
     
    The plasma instruments on board Solar Orbiter will determine the three-dimensional velocity distribution functions of the plasma ions and electrons with high time resolution, within heliocentric distances from ~0.3 to 1 au. The analysis of these distributions will determine the plasma bulk parameters (e.g., density, velocity, and temperature). New work by Nicolaou et al. (2019, 2020) assesses the accuracy of these measurements, considering the proton and electron instruments separately.
     
    1. The Impact of Turbulent Solar Wind Fluctuations on Proton Measurements

    The Solar Wind Analyser’s Proton Alpha Sensor (SWA-PAS) on board Solar Orbiter will measure solar wind plasma protons. However, due to the dynamic and turbulent nature of solar wind plasma, the accurate determination of the plasma parameters from the observations is significantly challenging. Nicolaou et al. 2019, simulated turbulent solar wind proton plasma that exhibits the typical features of turbulence spectrum. They modelled the expected observations by SWA-PAS (see Figure 1) and analyzed them using standard analysis methods in order to quantify the accuracy of the derived plasma bulk parameters. The results show that the typical turbulence will not significantly affect the accuracy of the high-time resolution measurements by SWA-PAS. In addition, the authors compare the accuracy of the instrument as a function of the acquisition time and discuss the sources of errors in the derived parameters.


    Time series of input data compared to modelled plasma moments

    Figure 1. Time series of modeled solar wind with a turbulent spectrum consisting of Alfvén waves and slow modes and a comparison to derived moment parameters from the expected SWA-PAS observations at lower resolution. Each panel shows the input data (gray line) and the moments derived from the modeled observations (bullets). The shadowed areas represent the time intervals in which the instrument collects counts to construct an entire 3D VDF. The top panel shows the plasma density the middle panel shows the diagonal elements of the plasma temperature tensor, and the bottom panel shows the plasma bulk speed. Besides the small systematic underestimation of the plasma density and plasma temperature, the derived moments suggest that the accuracy of SWA-PAS measurements, under typical turbulent solar wind conditions, is remarkably high.

     
    2. Determining the Bulk Parameters of Plasma Electrons from Pitch-Angle Distribution Measurements

    The Solar Wind Analyser’s Electron Analyser System (SWA-EAS) is designed to observe the solar wind electrons. In burst-mode operations, the instrument will obtain measurements in the 2D velocity space (as opposed to full 3D velocity distributions) in order to construct the pitch angle distributions of plasma electrons. The reduction of one dimension reduces the statistical significance of the observations and makes the analysis more challenging. Nicolaou et al. 2020, investigate the expected accuracy of the derived bulk parameters of supra-thermal electrons, which are often described by kappa distribution functions. They simulate the expected observations within the heliocentric distance range from 0.3 to 1 au and derive the plasma bulk parameters by fitting the synthetic observations (see Figure 2). The study shows that the proper fitting analysis of the measurements can derive the plasma parameters with significant accuracy, even at 1 au, where the expected particle flux is very low.
     

    A comparison of derived plasma parameters to input plasma density.

    Figure 2. (From top to bottom) The derived electron density over input density, kappa index, parallel and perpendicular temperature as functions of the input plasma density. The red points represent the mean values (over 200 samples) of the parameters derived by fitting only the measurements with Ci ≥ 1. The blue points represent the mean values of the parameters derived by fitting to all measurements including those with Ci = 0. The shadowed regions represent the standard deviations of the derived parameters. The dashed lines represent the input parameters.
     

    For more information, please see the papers:

    Nicolaou, G., Verscharen, D., Wicks, R. T., & Owen, C. J. (2019). The Impact of Turbulent Solar Wind Fluctuations on Solar Orbiter Plasma Proton Measurements. The Astrophysical Journal, 886:101. https://doi.org/10.3847/1538-4357/ab48e3

    Nicolaou, G., Wicks, R., Livadiotis, G., Verscharen, D., Owen, C., & Kataria, D. (2020). Determining the Bulk Parameters of Plasma Electrons from Pitch-Angle Distribution Measurements. Entropy, 22, 103. https://doi.org/10.3390/e22010103