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At Jupiter, isolated auroral patches have long been linked to particle injections from the magnetosphere. Here, the authors show that plasma waves can also scatter electrons into the atmosphere, triggering precipitation and producing aurora.

Magnetospheric substorms are powerful space weather events with debated onset mechanisms. Here, the authors show that new radio precursors of auroral kilometric radiation coincide with wave-like aurora and reveal Alfvénic processes before substorm onset.

JWST has detected \({{\rm{H}}}_{3}^{+}\) and auroral emissions at Neptune—the only giant planet in the Solar System for which they had proved to be elusive up to now. The observations reveal a factor-of-two cooling of Neptune’s upper atmosphere compared with Voyager 2 data, indicative of energy balance processes acting on a shorter timescale than solar forcing.

Geomagnetic substorms abruptly release energy, producing intense auroras and magnetic disturbances during an expansion phase. Here, the authors show this expansion is part of a global cycle of currents and plasma flows shaped by dayside and nightside reconnection.

There is a continuum emission component in the aurorae spectra that is unexplained. Here, the authors show gray-toned continuum emission structures associated with auroral dynamics explains previous continuum emission observations.

Two main acceleration mechanisms in the auroral acceleration region are electric potential and Alfvénic acceleration but associated energy dynamics are not completely resolved. Here, the authors show that Alfvén waves power the Earth’s auroral arc through a static potential drop in the auroral acceleration region.

High-resolution observations confirm that Jupiter’s global upper atmosphere is heated by transport of energy from the polar aurora.

The MAVEN spacecraft observed brightening in the Lyman-α line correlated with solar wind activity, which can be attributed to auroral activity by solar wind protons interacting with the Martian neutral hydrogen corona. Proton aurorae are normally seen at Earth only.

Substorms in the Earth’s magnetosphere lead to bright aurorae, releasing energy into the surrounding ionosphere. Ground- and space-based observations now reveal how that energy is dissipated and controlled by strong electric currents.

The detection of the auroral footprint of Jupiter’s moon Callisto is challenging, but a shift in Jupiter’s bright main auroral oval could provide an opportunity for potential detections. Here, the authors show observation of the ultraviolet footprint of Callisto using Juno spacecraft data, benefiting from such opportunity.

Whistler-mode chorus waves have been observed in the tail region of the terrestrial magnetosphere, where the magnetic field is not dipolar so that chorus waves were not expected, and their generation mechanisms have been tested with state-of-the-art observations.

Jupiter’s auroras visualise where energetic particles hit its upper atmosphere. Here, authors show JWST observations of Jupiter’s infrared auroras, revealing highly variable features and new auroral phenomena.

An updated rotation period of Uranus of 17.247864 ± 0.000010 h is derived from long-term Hubble Space Telescope images of its ultraviolet aurorae. The high accuracy of this value yields a new system III longitude model with improved long-term validity that could be used in planning future Uranus missions.

High-angular-resolution measurements allow the direct observation of the scattering of energetic electrons by chorus waves in the magnetosphere, which causes quasiperiodic electron precipitation that gives rise to pulsating aurorae.

Earth's diffuse aurora occurs over a broad latitude range, and is mainly caused by the precipitation of low-energy electrons originating in the central plasma sheet. Theory suggests that two classes of magnetospheric plasma waves — electrostatic electron cyclotron harmonic waves and whistler-mode chorus waves — could be responsible for the electron scattering that leads to diffuse auroral precipitation. Here it is found that scattering by chorus is the dominant cause of the most intense diffuse precipitation.

A pattern of features is detected, superposed on Saturn’s low-latitude infrared glow, that implies the transfer of charged species derived from water (ring ‘rain’) from the ring plane to the ionosphere, ultimately leading to the global modulation of upper atmospheric chemistry.

The process that generates Earth’s most intense aurora is found to occur at Jupiter, but is of only secondary importance in generating Jupiter’s much more powerful aurora.

Simulations show that the competing effects of the solar wind and planetary rotation can explain the structure of planetary aurorae: the former dominates for Earth-type and the latter for Jupiter-type aurorae, with the highly variable aurorae at Saturn representing a transition state.

Mesospheric ghosts are rare, faint, greenish transient luminous events. Here, the authors show metallic emissions revealed by the spectrum of a mesospheric ghost.

Jovian short bursts (S-bursts) are induced by the Io-Jupiter interaction. Here, the authors show a drifting radio burst detection method and report S-bursts related to Ganymede-Jupiter interaction and to Jovian aurora.

Although whistler-mode chorus waves are common in the Earth’s and other planetary magnetospheres, the mechanism behind fast frequency chirping is debated. Here, the authors show the presence of chorus emissions at Mars, with fundamentally the same nonlinear nature as those at Earth, despite vastly different magnetic and plasma conditions.

In our Solar System, whistler-mode chorus waves had been confirmed for all magnetized planets except Mercury. Finally, the first and second Mercury flybys in 2021 and 2022 by the BepiColombo/Mio spacecraft revealed chorus waves in the dawn sector.

Both magnetic reconnection and kinetic instabilities are required to produce magnetotail plasma eruptions, according to high-resolution global simulations of Earth’s magnetosphere.

New northern aurora emissions on Uranus in the infrared spectrum are detected after a 30-year search. The emissions, observed close to equinox, are most likely caused by the 88% increase in upper atmosphere column density.

Scattering by the upper- and lower-band chorus waves are the dominant cause of diffuse auroral precipitation. Here, the authors show that the lower-band chorus alone satisfies the preferred condition for the generation of second harmonics to trigger the diffuse auroral electron precipitation.

Solar wind observations from the Magnetospheric Multiscale mission reveal bursty, turbulent properties within a reconnection diffusion region, in contrast with the usual quasi-steady state of solar wind reconnection. Between October 2017 and May 2019 75 other similar events were identified, indicating the relevance of turbulent reconnection in the solar wind.

Excitation of whistler-mode waves by cyclotron instability is considered as the likely generation process of the waves. Here, the authors show direct observational evidence for locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves in Earth’s magnetosheath.

Far-UV observations from the Hubble Space Telescope provide evidence of water vapour in the tenuous atmosphere of Ganymede. Atmospheric water originates from surface ice sublimation, with an enrichment in the subsolar region and substantial asymmetry between the leading and trailing hemispheres.

It was predicted that Alfvén waves can account for the acceleration of precipitating auroral electrons. Here, the authors show laboratory measurements of the resonant transfer of energy from Alfvén waves to electrons under conditions relevant to the auroral zone as a direct test.

Energetic electron densities in the radiation belt increases during geomagnetic storms. Here, the authors show oblique whistler mode waves enhance electron losses and create strong fluxes of about 100 keV electrons precipitating into the atmosphere, that should be considered in radiation belt models.

During geomagnetic substorms, the energy accumulated from solar wind is abruptly transported to ionosphere. Here, the authors show application of community detection on the time-varying networks constructed from all magnetometers collaborating with the SuperMAG initiative.

The origin of geomagnetic substorms is still uncertain due to lack of comprehensive quantitative analyses. Here, the authors construct an observational dispersion relation of auroral forms that correspond to the explosive energy release from substorm onset.

Theoretical studies suggested that plasmapause surface waves related to the sharp inhomogeneity exist and act as a source of geomagnetic pulsations. Here, the authors show direct observations of a plasmapause surface wave and its impacts during a geomagnetic storm using multi-satellite and ground-based observations.

Seasonally averaged energy input into the ionosphere from geospace is generally considered to be symmetric. Here, the authors show preference for electromagnetic energy input at 450 km altitude into the northern hemisphere, on both the dayside and the nightside, when averaged over season.

Electron precipitation plays major role in magnetospheric physics and space weather. Here the authors show nonlinear behavior of the wave–particle interaction in the magnetosphere as the evolution of chorus electromagnetic waves detected by the Arase satellite and PWING observatory.

In situ measurements from the Rosetta spacecraft reveal the presence of atomic emissions close to comet 67P’s nucleus. Such emissions are due to dissociative excitation of molecules by the interaction with the solar wind, identifying them as a form of aurora.

Hurricanes in the Earth’s low atmosphere are known, but not detected in the upper atmosphere earlier. Here, the authors show a long-lasting hurricane in the polar ionosphere and magnetosphere with large energy and momentum deposition despite otherwise extremely quiet conditions.

The solar wind affects the magnetosphere, but whether this holds true for solar flares was unclear. By combining geospace modelling with observations, solar flares are shown to influence the dynamics of the magnetosphere and its ionosphere coupling.

An intensification of the 7.8-µm methane emission at Jupiter’s poles is observed in coincidence with the arrival of a solar-wind compression in January 2017, highlighting the strong coupling between Jupiter’s magnetosphere and its neutral stratosphere.

Magnetic reconnection in the near-Earth magnetotail is observed to power a space storm, although suppression of magnetic reconnection caused by the Earth’s magnetic dipole was expected close to Earth.