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The HiBAR rocket launched January 28, 2003 into the night-side aurora in order to measure high frequency radio waves with both parallel and perpendicular antennae. The rocket encountered several short high-frequency radio wave bursts with a secondary wave associated with them, believed to be a product of a nonlinear wave-wave interaction of the initial wave with observed lower frequency waves. Nonlinear waves are not often observed, and their dynamics are of significant interest.

Magnetospheric physics is at an extremely vibrant phase with a number of ongoing and highly-successful missions, e.g. Cluster, THEMIS, Van Allen Probes, and MMS spacecraft, providing the most amazing observations and data sets. Since there are many fundamental and unsolved problems, in this paper I have addressed selected topics of ULF wave - charged particle interactions, which encompass many special fields of radiation belt, ring current and plasmaspheric physics.

Auroral spirals known as northern lights are a spectacular light show in the polar night sky. We show that auroral spirals are produced in the polar ionosphere by the internal processes that ensure quasi-neutral equilibrium of the polar ionosphere which is often violated during field line dipolarization. The internal driver produces spiral auroras in a manner different from the field line mapping scenario.

We analyzed all-sky camera images observed at Mt. Bohyun observatory (36.2°N, 128.9°E) for the period of 2017–2019. We retrieved gravity wave parameters including horizontal wavelength, phase velocity and period from the image data. The horizontally propagating directions of the wave were biased according to their seasons, exerted with filtering effect by prevailing background winds. We also evaluated the nature of vertical propagation of the wave for each season.

The plasmaspheric plume is an important region of ‘detached plasma elements‘ and provides an effective coupling channel of energy/mass between the inner magnetospheric plasmasphere and outer magnetosphere. In the study, using VAP data, we present a statistical result of plasmaspheric plumes in the inner magnetosphere, which implies that the plumes tend to occur during the recovery phase of geomagnetic storms, and the occurrence rate is larger during stronger geomagnetic activity.

The Lehtinen-Pirjola method is widely used for modelling geomagnetically induced currents (GIC) in power systems but was developed when the main aim was to model GIC in only the highest voltage level of a power network. Here we present a modification to the Lehtinen-Pirjola (LP) method designed to provide an efficient method for modelling GIC in multiple voltage levels. We also show how existing software can easily be converted to the new method and provide examples of calculations.

This study showed the ionospheric response over low latitudes regions in Brazil predicted by Martínez-Ledesma et al. (2020) for the solar eclipse event on December 14, 2020. We used a multi-instrumental and modeling analysis to observe the modifications in the E and F regions and the Es layers over Campo Grande and Cachoeira Paulista. The results showed that solar eclipses can cause significant ionosphere modifications even though they only partially reach the Brazilian low latitude regions.

This paper presents observations of FTE-type flux ropes on the dayside during BepiColombo's Earth flyby FTE-type flux ropes are a well-known feature of magnetic reconnection on the magnetopause and they can be used to constrain the location of reconnection X-lines. Our study suggests that the magnetopause X-line crossed over BepiColombo from the north as it traversed the magnetopause. Moreover, it also strongly supports that coalescence can create larger flux ropes by combining smaller ones.

Revealing the nature of Mercury’s internal magnetic field is one of the primary goals of the BepiColombo mission. Besides the parametrization of the magnetic field contributions, the application of a robust inversion method is of major importance. The present work provides an overview of the most commonly used inversion methods and shows that Capon’s method as well as the Tikhonov regularization enable a high precision determination of Mercury’s internal magnetic field up to the fifth degree.

Using the Digisonde data, this paper shows that the small variation in the geomagnetic activity during low solar activity can affect both the parameter of height and frequency of the intermediate layer (ILs) over the low latitude Brazilian sector. The most expressive responses of the ILs to geomagnetic activity were during the summer when the height of the ILs suffered a significant decrease with the increase of the magnetic activity magnetic in the first hours of the day.

Radial diffusion mechanism is of outmost importance to both the acceleration and loss of relativistic electrons in the outer radiation belt and, consequently, for physics-based models, which provide nowcasting/forecasting of the electron population. In the framework of the SafeSpace project we have created a database of accurately calculated radial diffusion coefficients and, furthermore, we have exploited it to provide insights for future modelling efforts.