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.

Recently, the two-spacecraft mission BepiColombo was launched to explore Mercury. To measure the magnetic field precisely, in-flight calibration of the magnetometer offset is needed. Usually, the offset is evaluated from magnetic field observations in the solar wind. Since one of the spacecraft will remain within Mercury's magnetic environment, we examine an alternative calibration method. We show that this method is applicable and may be a valuable tool to determine the offset accurately.

This paper is the first to study how the representation of the magnetic-local-time (MLT) dependency of electron precipitation impacts middle-atmospheric-ozone response on monthly timescales. We use a state-of-the-art chemistry–climate model with detailed lower-ionospheric chemistry for an advanced representation of atmospheric impacts of electron forcing. We find that the use of daily zonal-mean electron forcing will provide an accurate ozone response in long-term climate simulations.

Electric fields in the atmosphere near dynamic aurora are important in the physics of the electric circuit within the Earth's magnetic field. Oxygen ions emit light as they move under the influence of these electric fields; the flow of this emission is used to find the electric field at high temporal resolution. The solution needs two other simultaneous measurements of auroral emissions to give key parameters such as the auroral energy. The electric fields increase with brightness of the aurora.

We have applied three different methods to examine the observability, both tracking and discovery, of near-Earth objects (NEOs) by the EISCAT 3D radar system currently under construction. There are, to our knowledge, no previous studies on the expected discovery rates of NEOs using radar systems. We show that it is feasible to regularly track NEOs and mini-moons. We also show it is possible to discover new NEOs and mini-moons with EISCAT 3D, something never before done with radar systems.

Effects of space weather events in technological systems were studied in the tropical region of Brazil by investigating the Bolivia–Brazil pipeline during space weather events with different intensities. The results presented significant corrosion levels during the 17 March 2015 geomagnetic storm and showed that the effects of space weather must be accounted for, even in low latitudes, since the lifetime of the pipelines can be reduced.

Anatolian aurora has been reviewed based on existing catalogs to establish a relationship between the aurora observations and past solar activity. There is no study dealing only with the historical aurora observations recorded in Anatolia and Constantinople. A considerable relationship is revealed between the aurora and past solar activity. High auroral activity around 774/775 and the Medieval grand maximum in the 1100s in Anatolia is quite consistent with the past solar variability.

Comprehensive analysis of a moderate substorm was performed using optical observations inside the auroral oval and in the polar cap, combined with data from satellites, radars, and ground magnetometers. The onset took place near the poleward boundary of the auroral oval that is not typical for classical substorms. The data fit to the near-tail current disruption scenario of the substorm onset. The role of the 15 min oscillations in the IMF Bz component in the substorm initiation is discussed.

Dust grains exist throughout our solar system. This dust is subject to destruction processes like sublimation and sputtering. Sputtering is the erosion of dust through the impact solar wind and can be very effective near the Sun. We performed calculations to find out how important the sputtering process is compared to the sublimation of dust. Recently launched spacecraft will probe the proximity of the Sun and measure the dust population. Our work will help to understand these measurements.

We compared trapped outer radiation belt electron fluxes to high-latitude precipitating electron fluxes during two interplanetary coronal mass ejections (ICMEs) with opposite magnetic cloud rotation. The electron response had many similarities and differences between the two events, indicating that different acceleration mechanisms acted. Van Allen Probe data were used for trapped electron flux measurements, and Polar Operational Environmental Satellites were used for precipitating flux data.