Related papers: Forbush Decreases during strong Geomagnetic Storms…
At least two mechanisms effectively transfer interplanetary magnetic field (IMF) disturbances into the atmosphere. First, the inflow of solar wind into the ionosphere at low latitudes significantly enhances the total vertical electron…
Interplanetary space is characteristically structured mainly by high-speed solar wind streams emanating from coronal holes and transient disturbances such as coronal mass ejections (CMEs). While high-speed solar wind streams pose a…
On October 28, 2003 an earthward-directed coronal mass ejection (CME) was observed from SOHO/LASCO imagery in conjunction with an X17 solar flare. The CME, traveling at nearly 2000 km/s, impacted the Earth on October 29, 2003 causing…
A detailed investigation was carried out to understand a prolonged (~44 hours) weakly southward interplanetary magnetic field (IMF-Bz) condition during May 02--04, 1998. In-situ observations, during the period, showed the passage of an…
Non-recurrent short term variations of the galactic cosmic-ray (GCR) flux above 70 MeV n$^{-1}$ were observed between 2016 February 18 and 2017 July 3 aboard the European Space Agency LISA Pathfinder (LPF) mission orbiting around the…
Interplanetary coronal mass ejections (ICMEs), the large-scale eruptive phenomena capable of shedding a huge amount of solar magnetic helicity and energy are potential in driving strong geomagnetic storms. They complexly evolve while…
More than 140 isolated non-recurrent geomagnetic storms (GMSs) of various intensities from extreme to weak are considered, which are reliably identified with solar eruptive sources (coronal mass ejections, CMEs). The analysis aims to obtain…
The Radiation Assessment Detector (RAD), on board Mars Science Laboratory's (MSL) Curiosity rover, has been measuring ground level particle fluxes along with the radiation dose rate at the surface of Mars since August 2012. Similar to…
A geomagnetic storm is the result of sustained interaction between solar wind with a southward magnetic field and the magnetosphere. To investigate the influence of various solar wind parameters on the intensity of major geomagnetic storm,…
After a very calm 24th solar activity cycle, the 25th cycle has already seen several interesting events. A Ground Level Enhancement GLE77 was observed on 11 November 2025 following an X5.1 class solar flare. A strong Forbush decrease…
Voyager 1 has explored the solar wind-interstellar medium interaction region between the terminal shock and heliopause following the intensity distribution of galactic cosmic ray protons above 200 MeV energy. Before this component reached…
Intense geomagnetic storms are characterized by a minimum value of the Dst index at or below -100 nT. It is well known that these storms are caused by the southward magnetic fields in coronal mass ejections (CMEs) and corotating interaction…
On 2017-09-10, solar energetic particles (SEPs) originating from the active region 12673 were registered as a ground level enhancement (GLE) at Earth and the biggest GLE on the surface of Mars as observed by the Radiation Assessment…
Forecasting the geomagnetic effects of solar coronal mass ejections (CMEs) is currently an unsolved problem. CMEs, responsible for the largest values of the north-south component of the interplanetary magnetic field, are the key driver of…
An unexpected strong geomagnetic storm occurred on 2018 August 26, which was caused by a slow coronal mass ejection (CME) from a gradual eruption of a large quiet-region filament. We investigate the eruption and propagation characteristics…
This study investigates the modulation of particle fluxes at the Earths surface influenced by the intensity and orientation of the Interplanetary magnetic field (IMF) carried by the Coronal Mass Ejecta (ICME). We examine how IMF and its Bz…
Ground-level enhancements (GLEs) generally accompany with fast interplanetary coronal mass ejections (ICMEs), the shocks driven by which are the effective source of solar energetic particles (SEPs). In the GLE event of 2000 July 14,…
On July 25 2017 a multi-step Forbush decrease (FD) with the remarkable total amplitude of more than 15\% was observed by MSL/RAD at Mars. We find that these particle signatures are related to very pronounced plasma and magnetic field…
This work shows an anomalously enhanced response of the low-latitude ionosphere over the Indian sector under weak geomagnetic conditions (October 31, 2021) in comparison to a stronger event (November 04, 2021) under the influence of an…
Improving predictions of the geomagnetic impact of coronal mass ejections (CMEs) requires understanding how solar source properties relate to in-situ measurements at Earth. However, major geomagnetic storms frequently arise from interacting…