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.

The Low Orbit Pearl Satellites measure magnetic field with high spatial coverage. Although there is no magnetic cleanliness to the satellites, the triple sensor configuration enables removal of interference. Results show they can capture the Earth’s internal as well as external fields from the magnetosphere–ionosphere current system. This study implies that a large number of small low-cost satellites without magnetic cleanliness could be the future for space magnetic exploration.

We present a new in situ observation of energetic electrons in space obtained by a newly available particle detector. In view of the characteristic signatures in the particle flux, we attribute the observational features to the drift-resonance wave–particle interaction between energetic electrons and multiple localized ultra-low-frequency waves. The scenario is substantiated by a numerical calculation based on the revised drift-resonance theory which reproduced the observed particle signatures.

The features of ULF waves are statistically studied on the magnetotail stretched magnetic field lines (8 RE < R < 32 RE) by using 8 years of THEMIS data. The occurrence rates of ULF waves are higher in the post-midnight region than pre-midnight region. The frequency decreases with increasing radial distance of 8–16 RE and could be explained by much more standing waves in this region than in the region of 16–32 RE. The wave frequency is higher after the substorm onset than before it.