MIST

Magnetosphere, Ionosphere and Solar-Terrestrial

Latest news

STFC Public Engagement Early-Career Researcher (PEER) Forum

The STFC has issued a call for applications to join their Public Engagement Early-Career Researcher (PEER) Forum, which is designed to support talented scientists and engineers in the early stages of their career in developing their public engagement and outreach goals. This forum is geared towards PhD students and early-career postdocs developing ideas for public engagement with similarly-minded researchers in a context that allows them to feed suggestions for the improvement of STFC's programmes back to STFC itself, and involves meeting twice a year. The deadline for applications is 4pm on 3 June 2019. For more information and more detail on what the scheme involves, you can visit the PEER Forum webpage or This email address is being protected from spambots. You need JavaScript enabled to view it..

The aims of the PEER Forum are as follows:

  • To foster peer learning and peer support between early career scientists and engineers with a passion for public engagement and outreach.
  • To improve understanding of the support STFC provides for public engagement and outreach (including funding mechanisms, evaluation, and reporting) and how to successfully utilise this support.
  • To stimulate discussions that help to develop and influence STFC’s approaches to public engagement.

ESA Science Programme Committee greenlights SMILE

The Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) has been given the green light for implementation by ESA's Science Programme Committee. SMILE will explore the Sun-Earth connection in a very novel way, by mapping solar wind-magnetosphere interactions in soft X-rays. SMILE is a joint mission by ESA and the Chinese Academy of Sciences (CSA). The UK is one of many countries contributing to the payload development.

The SMILE payload comprises four instruments: a soft X-ray imager (SXI), a UV auroral imager (UVI) and an in situ measurement package composed of a light ion analyser and a magnetometer. The UK leads SXI, Canada leads UVI, and China leads the ion analyser and magnetometer. SMILE will fly in a highly elliptical polar orbit with an apogee of 20 Earth radii to image the magnetosphere and the Northern Lights for more than 40 hours continuously per orbit. The launch is planned in November 2023.

For more information, visit the European Space Agency, the Chinese Academy of Sciences, or Mullard Space Science Laboratory.

Debye mission proposal for ESA F-class call

We are currently preparing a proposal for the space mission “Debye” in response to ESA’s F-Class call. As the first dedicated electron-astrophysics mission, Debye will use the solar wind as a testbed to study universal small-scale electron processes throughout the universe. The mission's key science question is: “How are electrons heated in astrophysical plasmas?”
 
Debye will consist of up to four spacecraft that will orbit the Lagrange point L2. The main spacecraft will measure electron distribution functions with unprecedented cadence and very high resolution, electric fields, magnetic fields, and plasma ions. The deployable spacecraft will provide multi-point and multi-baseline measurements of the magnetic field to determine the nature of fluctuations on electron scales.
 
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RAS Specialist Discussion suggestions invited

The RAS is inviting suggestions from Fellows of the RAS for Specialist Discussion meeting topics in the academic year 2019/20. These meetings are held on the second Friday of the month between October and May in a given academic year; the April meeting will be moved due to the second Friday being Good Friday. 

If you would like to organise one of these meetings, you can do so by submitting a proposal no longer than one A4 page. Geophysics proposals, including MIST science, should be sent to This email address is being protected from spambots. You need JavaScript enabled to view it., and the deadline is 1 March 2019.

Your proposal should include the title of the meeting; the names of the co-convenors (at least one of whom should be a RAS Fellow); the topics you intend to cover; the rationale (including timeliness); suggestions for invited speakers; and the preferred date for the meeting. More information, including detailed guidance, can be found on the RAS website.

 

RAS awards for 2019 announced

MIST Council would like to extend their congratulations to the 2019 Royal Astronomical Society award winners, as well as the recent AGU award winners. In particular, we congratulate the following MIST members recognised for their significant achievements:
  • Margaret Kivelson (UCLA) has been awarded the Gold Medal in Geophysics for a lifetime of outstanding achievement in understanding planetary magnetospheres and their connections to the planets they surround.
  • Tom Stallard (Leicester) has been awarded the Chapman medal in Geophysics for outstanding contributions to understanding planetary upper atmospheres and their interactions with their magnetospheres.
  • The Cluster Science and Operations Team have been awarded the Geophysics Group Award for their continued success ensuring the operations and scientific exploitation of the European Space Agency’s Cluster mission.
  • Mark Clilverd (British Antarctic Survey) has been awarded the James Dungey Lecture for their excellent research on energetic particle precipitation and its effects on the upper atmosphere and climate, and their vast experience delivering outstanding scientific talks to a broad range of audiences.
  • Julia Stawarz (Imperial College London) has been awarded the Basu United States Early Career Award for Research Excellence in Sun-Earth Systems Science for significant contributions in furthering understanding of collisional plasma turbulence and kinetic scale processes. 
MIST Council would also like to congratulate Fran Bagenal (Colorado), who has been awarded the AGU Van Allen Lecture for exceptional work on the understanding of planetary magnetospheres and outstanding contributions to planetary missions.

Equatorial magnetosonic waves observed by Cluster satellites: The Chirikov resonance overlap criterion

by Homayon Aryan (University of Sheffield)

Numerical codes modelling the evolution of the radiation belts often account for wave-particle interaction with magnetosonic waves. The diffusion coefficients incorporated in these codes are generally estimated based on the results of statistical surveys of the occurrence and amplitude of these waves. These statistical models assume that the spectrum of the magnetosonic waves can be considered as continuous in frequency space, however, this assumption can only be valid if the discrete nature of the waves satisfy the Chirikov resonance overlap criterion.

The Chirikov resonance overlap criteria describes how a particle trajectory can move between two resonances in a chaotic and unpredictable manner when the resonances overlap, such that it is not associated with one particular resonance [Chirikov, 1960]. It can be shown that the Chirikov resonance overlap criterion is fulfilled if the following equation is satisfied:

δθ = (vl / tanθm) / (1 - (ω2/ce2))

where θm is the mean angle between the propagation direction and the external magnetic field, δθ is the standard deviation of the wave propagation angles , l is the harmonic number, v=me/mp is the electron to proton mass ratio, and Ωce is the electron gyro-frequency [Artemyev et al., 2015].

Here we use Cluster observations of magnetosonic wave events to determine whether the discrete nature of the waves always satisfy the Chirikov resonance overlap criterion, extending a case study by Walker et al. [2015]. An example of a magnetosonic  wave event is shown in panels a-c of the Figure. Panel d shows that the Chirikov overlap criterion is satisfied for this case. However, a statistical analysis shows that most, but not all, discrete magnetosonic emissions satisfy the Chirikov overlap criterion. Therefore, the use of the continuous spectrum, assumed in wave models, may not always be justified. We also find that not all magnetosonic wave events are confined very close to the magnetic equator as it is widely assumed. Approximately 75% of wave events were observed outside 3° and some at much higher latitudes ~21° away from the magnetic equator. This observation is consistent with some past studies that suggested the existence of low-amplitude magnetosonic waves at high latitudes. The results highlight that the assumption of a continuous frequency spectrum could produce erroneous results in numerical modelling of the radiation belts.

For more information please see the paper below:

Aryan, H., Walker, S. N., Balikhin, M. A., & Yearby, K. H. ( 2019). Equatorial magnetosonic waves observed by Cluster satellites: The Chirikov resonance overlap criterion. Journal of Geophysical Research: Space Physics, 124. https://doi.org/10.1029/2019JA026680

Figure: Observation of a magnetosonic wave event measured by Cluster 2 on 16 November 2006 at around 02:08 to 02:33~UT. The top three panels (a, b, and c) show the dynamic wave spectrogram (Bx, By, and Bz respectively) measured by STAFF search coil magnetometer. Panel d shows the analysis of the Chirikov resonance overlap criterion outlined in equation shown on top-left of the panel. The blue and red dots represent 10~s averaged values of dqand the ratio on the right hand side of equation respectively.