The boundary of Earth's magnetic field, the magnetopause, deflects and reacts to the solar wind - the energetic particles emanating from the Sun. We find that certain types of solar wind favour the occurrence of deviations between the magnetopause locations observed by spacecraft and those predicted by models. In addition, the turbulent region in front of the magnetopause, the foreshock, has a large influence on the location of the magnetopause and thus on the accuracy of the model predictions.

In our study, we looked at the boundary between the Earth's magnetic field and the interplanetary magnetic field emitted by the Sun, called the magnetopause. While other studies focus on the magnetopause motion near Earth's Equator, we have studied it in polar regions. The motion of the magnetopause is faster towards the Earth than towards the Sun. We also found that the occurrence of unusual magnetopause locations is due to similar solar influences in the equatorial and polar regions.

We derive the wave–particle interaction time (IT) equation considering the effects of special relativity theory for whistler-mode chorus waves and relativistic electrons in Earth's radiation belt. Results show that IT has a non-linear dependence on the wave group velocity, electrons' energy, and initial pitch angle. Our results show that the interaction time is generally longer when applying the complete relativistic approach compared to a non-relativistic calculation.

In this study, we use a multipoint analysis of conjugate magnetospheric and ionospheric observations to investigate the magnetospheric and ionospheric responses to fast flow bursts that are associated with different space weather conditions. The results show that ionospheric currents are connected to the magnetospheric flows for different space weather conditions. The connection is more apparent and global for flows that are associated with a geomagnetically active condition.

We used multipoint magnetic field, electric field, plasma, and energetic particle observations to study the spatial, temporal, and spectral characteristics of compressional Pc5 pulsations observed deep within the magnetosphere at the end of a strong magnetic storm. We investigated the mode of the waves and their nodal structure. The energetic particles responded directly to the compressional Pc5 pulsations. We interpret the compressional Pc5 waves in terms of drift-mirror instability.