MIST

Magnetosphere, Ionosphere and Solar-Terrestrial

Latest news

New MIST Chair and Vice-Chair elected

Congratulations to John Coxon on becoming MIST Chair, and to Jasmine Sandhu on becoming MIST Vice-chair in a unanimous vote at a Council meeting last week.
 
MIST Council elects a new Chair whenever the previous Chair steps down, and in addition this year, the council has decided to elect a Vice-Chair for the first time.
 
On behalf of the MIST community, we would like to thank Ian McCrea for doing a superb job as Chair during his tenure on the Council.

EGU elections now open

The call for candidates for the EGU 2019 elections is currently open, with a deadline of 15 September 2019. The following roles are up for election: Union President, General Secretary, and the Division Presidents. More details about these roles and how you can nominate yourselves/colleagues can be found on the EGU website. 
 
MIST Council would like to emphasise that this is an excellent opportunity to contribute to and shape the field on an international scale, and we hope to see members from the MIST community putting themselves forward.

Summer Science Exhibition 2020

The Royal Society is currently accepting proposals for the Summer Science Exhibition 2020, and the deadline for proposals is 10 September 2019. Further details on applying can be found here.
 
MIST Council would like to highlight that this is an excellent opportunity for cross-institutional collaborations! The MIST community is involved in a number of projects with a particularly timely aspect (e.g. Solar Orbiter and SMILE), which would be very appropriate to propose to the Royal Society. If you are currently preparing a proposal that you are happy to invite community members to join or you have an idea for a proposal that you would like to work with the community on, then please email This email address is being protected from spambots. You need JavaScript enabled to view it. with a short outline by 9 August 2019. We hope to then share these projects with the community to build support for the proposals and involve the wider community!
 
We will be discussing this further and sharing ideas on the #public-engagement channel on the MIST Slack workspace. If you aren’t on the MIST Slack workspace then click here for details.

2019 Rishbeth prize winners announced

We are pleased to announce that the Rishbeth Prizes this year are awarded to Affelia Wibisono and Michaela Mooney , both of the Mullard Space Science Laboratory (UCL).
 
Affelia Wibisono wins the prize for the best MIST student talk, entitled “Jupiter’s X-ray Aurorae as seen by XMM-Newton concurrently with Juno”. Michaela wins the best MIST poster prize, for a poster entitled “Evaluating auroral forecasts against satellite observations”.
 
MIST Council would like to congratulate both Affelia and Michaela. As prize winners, Affelia and Michaela have been invited to write articles for Astronomy & Geophysics, which we look forward to reading.

Call for MIST/GEM Liaisons

There is a potential opening for a member of the MIST community to act as a liaison with the GEM (Geospace Environment Modelling) group. This will be an opportunity to act as a representative of the UK MIST community and inform GEM about relevant activities within the MIST community.

GEM liaisons will typically have the following responsibilities:

  1. Attend​​ a preponderance ​​of ​​GEM Steering ​​Committee ​​meetings​ ​at ​​summer​ ​workshop and​ ​mini-GEM​ ​​(June​ ​and​ ​December)
  2. Provide​​ written​​ annual​​ report​​ to​​ GEM Communications ​​Coordinator​​​ (by ​​April)
  3. Help ​​recruit ​​new​ ​GEM Steering​ ​Committee ​​members ​​​(as ​​needed)
  4. Provide ​​feedback​​ from​​ the​​ MIST community ​​and​​ share​​ with the GEM Chair/Vice​ ​Chair​ ​​(ongoing)

At this stage we would like to welcome any expressions of interest for this role from the community. If you are interested in being a GEM Liaison, then please This email address is being protected from spambots. You need JavaScript enabled to view it. including up to 100 words detailing why you would like to be a liaison and how your experience equips you for this role, and how often you would be able to attend GEM meetings.

If you have any further questions or would like more information about what the role would entail then please get in touch!

Detecting the Resonant Frequency of the Magnetosphere with SuperDARN

by Samuel J. Wharton (University of Leicester)

The Earth’s magnetosphere is constantly being disturbed by ultralow frequency (ULF) waves. These waves transport energy and momentum through the system and can form standing waves on magnetospheric field lines. These standing waves have a resonant frequency which depends on the magnetic field strength and plasma distribution along the field line. The waves result in perturbations in the magnetic field and plasma in the ionosphere. These occur at the resonant frequency and can be directly observed with instruments on the ground. Being able to measure the resonant frequency can provide valuable information about the state of the magnetosphere.

Traditionally, this can be done by applying a cross-phase spectral technique to ground-based magnetometers. It works by finding the frequency where the phase change with latitude is most rapid. This occurs at the local resonant frequency.

The Super Dual Auroral Radar Network (SuperDARN) is a global consortium of 35 radars that observe radio waves backscattered from the ionosphere. The radars detect ULF waves by observing the movements of ionospheric plasma.

For the first time, we have applied the cross-phase technique to SuperDARN. These radars have a much greater spatial resolution and coverage and provide more detailed information than can be achieved with magnetometers alone. In this study, we have used some notable techniques, such as developing a Lomb-Scargle cross-phase technique for uneven data and exploiting an improved fitting procedure Reimer et al. (2018).

We have been able to apply these methods to several examples and validate the results with ground magnetometer estimations. When available, ionospheric heaters can be used to reduce the uncertainty in the backscatter location. However, the majority of SuperDARN data does not have a heater in the field of view and observes ‘natural scatter’. Figure 1 shows an example of the technique applied to natural scatter. The red band in Figure 1e lies at the resonant frequency. Hence, we can measure the resonant frequencies with and without an ionospheric heater.

This study demonstrates that SuperDARN can be used as a tool to monitor resonant frequencies and therefore the plasma distribution of the magnetosphere. This opens up a new application for the SuperDARN radars.

For more information, please see the paper below:

Wharton, S. J., Wright, D. M., Yeoman, T. K., & Reimer, A. S. (2019). Identifying ULF wave eigenfrequencies in SuperDARN backscatter using a Lomb-Scargle cross-phase analysis. Journal of Geophysical Research: Space Physics, 124. https://doi.org/10.1029/2018JA025859

Figure 1: This shows an example of the local resonant frequency being measured by SuperDARN. (a) and (b) show range-time-intensity plots for beams 12 and 15 of the Þykkvibær radar. (c) shows filtered line-of-sight velocities for range gates 10 and 9 on those beams respectively. (d) The cross-phase spectrum for data in (c). (e) The cross-phase spectrum from (d) smoothed.