Recent  

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.

The relationships between the auroral activity and the solar-wind conditions are modeled with a machine lerning technique. The impact of various solar-wind parameters on the auroral activity is then evaluated by putting artificial inputs into the trained machine learning model. In particular, nonlinear effects of the solar-wind density are suggested.

To study long-term trends in the mesosphere and lower thermosphere (70–100 km) we established two summer length definitions and analyzed the variability over the years (2004–2020). After the analysis, we found significant trends in the summer beginning of one definition. Furthermore, we were able to extend one of the time series up to 31 years, and we obtained evidence of non-uniform trends and periodicities similar to those known for quasi-biennial oscillation and El Niño-southern oscillation.

This article is about using remote sensing data to estimate the date and magnitude of the impending earthquakes. An earthquake can also affect the environment. Damage to the environment can destroy and lose lives and be more dangerous than earthquakes. The damage sustained by earthquakes is due to the secondary effects of man-made materials on the environment. Water pipes are broken and the ground is flooded, and gas, electricity and scattered fuel lines cause fires.

We developed a new approach for validation the numerical models of electromagnetic wave propagation in the Earth-ionosphere waveguide. We compared the parameters of the waveguide (i.e., characteristic electric and magnetic altitudes, resonance frequencies, phase velocity and attenuation rate) obtained from numerical model with correspondent analytical calculations. We tested such validation for various conductivity profiles and find good agreement between analytical and numerical results.

A rare gravity wave event was observed on the night of 25 April 2017 over northern Germany. An all-sky airglow imager recorded an upward propagating wave at different altitudes in mesosphere with a prominent wave front above 91 km and faintly observed below. Based on wind and satellite borne temperature profiles close to the event location, we have found the presence of a leaky thermal duct layer in 85–91 km. The appearance of this duct layer caused the wave amplitudes to diminish below 91 km.

Although the 1991 eruption of Mt Pinatubo had a severe impact on earths climate, the effect of this event on the mesosphere is not well understood. We investigated satellite-borne temperature measurements from the HALOE instrument and found indications that a positive temperature anomaly is present in the tropical upper mesosphere at the beginning of the HALOE time series, which may be related to the eruption of Mt. Pinatubo.