Search Publications
What Is Unusual About the Third Largest Geomagnetic Storm of Solar Cycle 24?
Gopalswamy, N.; Yashiro, S.; Mäkelä, P. +4 more
We report on the solar and interplanetary (IP) causes of the third largest geomagnetic storm (26 August 2018) in solar cycle 24. The underlying coronal mass ejection (CME) originating from a quiescent filament region becomes a 440 km/s magnetic cloud (MC) at 1 au after ∼5 days. The prolonged CME acceleration (for ∼24 hr) coincides with the time pr…
Magnetosheath Jet Occurrence Rate in Relation to CMEs and SIRs
Geyer, Paul; Temmer, Manuela; Plaschke, Ferdinand +6 more
Magnetosheath jets constitute a significant coupling effect between the solar wind (SW) and the magnetosphere of the Earth. In order to investigate the effects and forecasting of these jets, we present the first-ever statistical study of the jet production during large-scale SW structures like coronal mass ejections (CMEs), stream interaction regi…
Three-Dimensional Structure of the Corona During WHPI Campaign Rotations CR-2219 and CR-2223
Lamy, P.; Gilardy, H.; Nuevo, F. A. +6 more
Differential emission measure tomography (DEMT) and white light (WL) tomography were applied to study the three-dimensional (3D) structure of the global solar corona for two Whole Heliosphere and Planetary Interactions campaign periods, Carrington rotations 2219 and 2223. With DEMT, Solar Dynamics Observatory/Atmospheric Imaging Assembly images we…
On the Global Kinematic Positioning Variations During the September 2017 Solar Flare Events
Nie, Wenfeng; Rovira-Garcia, Adria; Wang, Yong +3 more
Several X-class solar flares (SFs) with different intensities and locations on the solar disk occurred in September 2017. Among them, the X9.3 SF on 6 September 2017 was the most intensive SF in the 24th solar cycle. In this study, we investigated and compared the ionospheric response to the different X-class SFs and their impacts on the Global Po…
Comparing and Contrasting the Properties of the Inner Heliosphere for the Three Most Recent Solar Minima
Downs, Cooper; Riley, Pete; Linker, Jon A. +2 more
The previous three solar cycles have ended in progressively more quiescent conditions, suggesting a continual slide into an ever deeper minimum state. Although the Sun's magnetic field is undoubtedly responsible for this quiescence, it is not clear how changes in its structure and strength modulate the properties of the solar wind. In this study, …
Solar Wind Velocities at Comets C/2011 L4 Pan-STARRS and C/2013 R1 Lovejoy Derived Using a New Image Analysis Technique
Jones, Geraint H.; Ramanjooloo, Yudish
The ion tails of bright comets have long been considered as a natural tracers of the solar wind (SW) near these objects. Studies of comets and their ion tails allow inexpensive monitoring of key SW structures in the inner heliosphere, much of which is otherwise only accessible by in situ SW spacecraft measurements. Here, we present a novel techniq…
Reply to Comment by Stauning on "The PC Index Variations During 23/24 Solar Cycles: Relation to Solar Wind Parameters and Magnetic Disturbances"
Sormakov, D. A.; Troshichev, O. A.; Dolgacheva, S. A. +1 more
The polar cap magnetic activity index (PC) was approved by IAGA as an index characterizing the solar wind energy input into the magnetosphere. Relation of the PC index to solar wind parameters and solar activity during 23/24 solar cycles has been studied in paper (Troshichev et al., 2021, https://doi.…