This open session traditionally invites presentations on all aspects of the Earth’s magnetospheric physics, including the magnetosphere and its boundary layers, magnetosheath, bow shock and foreshock as well as solar wind-magnetosphere-ionosphere coupling. We welcome contributions on various aspects of magnetospheric observations, remote sensing of the magnetosphere’s processes, modelling and theoretical research. The presentations related to the current and planned space missions and to the value-added data services are also encouraged. This session is suitable for any contribution which does not fit more naturally into one of the specialised sessions and for contributions of wide community interest.

The Earth's magnetosphere can be significantly affected by transient solar wind features. Important energy transfer and transport will occur during the interaction of transient solar wind features with the Geospace system. Solar energy in various forms can propagate into the magnetosphere and ionosphere. Charged particle energy can be transformed to electromagnetic energy and vice versa. In-depth understanding of how the magnetosphere responds to transient solar wind features will enhance our knowledge on the solar wind - magnetosphere –ionosphere coupling.

This special session will address the processes by which solar wind mass, momentum, and energy enter the magnetosphere. Regions of interest include the foreshock, bow shock, magnetosheath, magnetopause, and cusps, the dayside magnetosphere, and both the dayside polar and equatorial ionosphere. This special session will provide a forum to present the latest results from in-situ spacecraft observations, ground-based observations, and global simulations. Coordinated multi-point observations are especially encouraged.

Magnetic reconnection is a fundamental process in space, astrophysics and laboratorial plasmas that explosively converts magnetic energy into kinetic energy of charged particles. Thanks to recent spacecraft missions, e.g, Cluster, THEMIS, MMS, etc, and the development of the computing simulations, many new findings have been obtained last several years. Also, many important issues remain: the triggering mechanisms, quantitative aspects of the energy conversions, identification of the electron diffusion region, electron acceleration mechanisms, and so on. This session invites presentations on all of the aspects associated with magnetic reconnection from the spacecraft measurements, the simulations, laboratory experiments and the theoretical analysis.

When Coulomb collisions between particles become negligible in a plasma, the particle distribution functions do not easily relax to Maxwellian distributions, and the MHD formalism fails to appropriately describe the plasma. Several processes, including magnetic reconnection, wave-particle interactions at kinetic scales, or turbulent cascading become the dominant mechanisms for energy exchange between populations and plasma regions in this regime. The Earth's magnetosphere and magnetosheath are composed of fully ionized, collisionless, plasmas. They constitute a natural laboratory for investigating these processes, which are generally non-linear. We invite abstracts discussing the kinetic nature of the plasma processes that occur in the Earth's magnetosphere and its surroundings. We encourage studies taking advantage of spacecraft measurements (e.g., MMS, Van Allen Probes, ARASE, THEMIS, Cluster, Geotail), modelling using kinetic simulations (e.g, Particle-In-Cell, Vlasov equation solvers) as well as analytical works.

The state of the magnetosphere is controlled mainly by solar wind conditions. The interplanetary magnetic field (IMF) as well as solar wind plasma parameters regulate the energy input into the magnetosphere. The direction of the IMF plays an important role in the coupling between the solar wind and magnetosphere. For example, during northward IMF conditions, the coupling is more complex, consisting of lobe reconnection as well as plasma transfer due to Kelvin-Helmholtz waves at the magnetospheric flanks. Quasi-radial IMF results in the formation of a foreshock upstream from the dayside magnetosphere, high-speed jets in the magnetosheath and magnetopause deformation. Magnetopause reconnection provides magnetic flux to the magnetotail, while substorms release magnetic energy stored within the magnetotail into the kinetic energy of accelerated particles. There are many different dynamic regimes or modes for the magnetosphere, including the quiet magnetosphere, steady magnetospheric convection, sawtooth oscillations, substorms, and storms. Transitions between these modes may result from changes in the upstream solar wind conditions, be the consequence of internal magnetospheric dynamics, and/or ionospheric feedback. As field-aligned currents couple the magnetosphere and ionosphere, the behaviours of the magnetosphere and ionosphere are closely related. Global magnetospheric dynamics can be studied by means of numerical simulations (MHD or kinetic), using empirical and semi-empirical models, or with the help of multipoint spacecraft observations. Besides, some past and future space missions can make global magnetospheric imaging providing information about positions and dynamics of the magnetospheric boundaries. One such example is the ESA/CSA Solar Wind Magnetosphere Ionosphere Link Explorer (SMILE) mission bringing into space the soft X-ray imager (SXI) and ultraviolet imager (UVI) as well as in situ instruments will be launched in 2023. We welcome any work presenting results on the global dynamics of the Earth’s magnetosphere as well as other planets’ magnetospheres.

The Earth's inner magnetosphere contains different charged particle populations, such as the Van Allen radiation belts, ring current particles, and plasmaspheric particles. Their energy range varies from eV to several MeV, and the interplay among the charged particles provide feedback mechanisms which couple all those populations together. Ring current particles can generate various waves, for example, EMIC waves and chorus waves, which play important roles in the dynamic evolution of the radiation belts through wave-particle interactions. Ring current electrons can be accelerated to relativistic radiation belt electrons. Plasmaspheric particles can also affect these processes. In addition, precipitation of ring current and radiation belt particles will influence the ionosphere, while up-flows of ionospheric particles can affect dynamics in the inner magnetosphere. Understanding these coupling processes is crucial.

While the dynamics of outer planets’ magnetospheres are driven by a unique combination of internal coupling processes, these systems have a number of fascinating similarities which make comparative studies particularly interesting. We invite a broad range of theoretical, modelling, and observational studies focusing on the dynamics of the inner magnetosphere of the Earth and outer planets, including the coupling of the inner magnetosphere and ionosphere and coupling between the solar wind disturbances and various magnetospheric processes. Contributions from all relevant fields, including theoretical studies, numerical modelling, observations from satellite and ground-based missions are welcome. In particular, we encourage presentations using data from MMS, THEMIS, Van Allen Probes, Arase (ERG), Cluster, cube-sat missions, Juno, SuperDARN, magnetometer, optical imagers, and IS-radars.

Electromagnetic waves permeate all regions of the planetary environments throughout the heliosphere, representing a unique mechanism of energy transfer in the nearly collisionless plasmas present. At Earth they play a fundamental role in the dynamics of the Van Allen radiation belts and ring current, being responsible for the particle acceleration, transport and loss. Planetary magnetospheres are highly variable systems, whose reactions to specific solar wind driving conditions can lead to important phenomena such as substorms. Considering that magnetospheric processes are ultimately driven by the solar wind, the ability to accurately forecast the trapped particle populations and magnetospheric dynamics is further dependent on understanding the coupling with external regions (e.g. solar wind, foreshock, magnetosheath).

The aim of this session is to discuss the generation and propagation of electromagnetic emissions in various frequency ranges (ULF, ELF, VLF), wave-particle interactions taking place, and the role of substorms in the dynamics of energetic particles trapped in the magnetospheres throughout the solar system. Theoretical and model contributions, as well as observational studies using data from recent satellite missions (Cluster, MMS, THEMIS, Van Allen Probes, ERG-Arase, etc.) and ground-based instruments at Earth as well as other planetary environments are encouraged.

This open session covers all aspects of small solar system objects, e.g., comets, asteroids, meteoroids, and dust. Topics include, but are not limited to, dynamics, evolution, physical properties, composition, detection, charging, heating, surface analysis, and further interactions. You are invited to present results obtained from space missions, remote sensing observations, laboratory studies, theory, and numerical simulations. This session also provides a forum for presenting future space missions and instrumentation. We encourage researchers with inter- and multi-disciplinary results.

Solicited contribution will be given by Stavro L. Ivanovski from National Institute for Astrophysics (Italy) on "The latest (dusty) pieces in the Rosetta story."