Results 41 to 50 of about 237 (168)

Improving Geomagnetic Perturbation Forecasts in the Southern Hemisphere via Kernel‐Based Encoding of Mirror Symmetry

Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 4, August 2026.
Abstract Accurate forecasting of geomagnetic perturbations is essential for assessing space weather risk of geomagnetic activities. Thanks to decades of magnetometer observations from world‐wide distributed networks and upstream solar wind observations at L1, data‐driven modeling of global geomagnetic perturbations has become increasingly feasible ...
Hongfan Chen, Gabor Toth, Yang Chen, Shasha Zou, Xun Huan   +4 more
wiley   +1 more source

A 3D Nonequilibrium Ionization Model of a Shock Wave in the Low Corona. I. Extreme-ultraviolet Emission and Inefficient Electron Heating

The Astrophysical Journal
Shocks in the low corona are best observed in the extreme ultraviolet (EUV); however, time-dependent ionization in the postshock region is generally incompatible with the otherwise straightforward plasma diagnostics typically applied to EUV imaging data.
Nicolas Trueba, John C. Raymond, Cooper Downs, Susan T. Lepri, Katharine K. Reeves, Yeimy J. Rivera, Maurice L. Wilson, Chengcai Shen   +7 more
doaj   +1 more source

Real‐Time Prediction of Two Geomagnetic Storms Using Solar Orbiter as a Far Upstream Solar Wind Monitor

Space Weather, Volume 24, Issue 8, August 2026.
Abstract We present the first real‐time predictions of coronal mass ejection (CME) magnetic structure and resulting geomagnetic impact at Earth for two events using far‐upstream observations from Solar Orbiter during March 2024. While our approach assumes idealized conditions for CME propagation and scaling, in situ magnetic field data from upstream ...
Emma E. Davies, Eva Weiler, Christian Möstl, Satabdwa Majumdar, Hannah T. Rüdisser, Timothy S. Horbury, Helen O'Brien, Jean Morris, Alastair Crabtree   +8 more
wiley   +1 more source

Large-amplitude Whistler Precursors and >MeV Particles Observed at a Weak Interplanetary Shock by Parker Solar Probe

The Astrophysical Journal
We report observations of an interplanetary (IP) shock observed by Parker Solar Probe (PSP) on 2024 September 29 at ∼07:50:29 UTC. PSP was only ∼17.07 R _s from the Sun, making this one of the closest observed IP shocks to date. The IP shock was a weak (
Lynn B. Wilson III, J. Grant Mitchell, Adam Szabo, Immanuel C. Jebaraj, Michael L. Stevens, David M. Malaspina, Grant D. Berland, Athanasios Kouloumvakos, Stuart D. Bale, Roberto Livi, Jasper S. Halekas, Christina M. S. Cohen   +11 more
doaj   +1 more source

A Type II Radio Burst Driven by a Blowout Jet on the Sun

The Astrophysical Journal, 2023
Type II radio bursts are often associated with coronal shocks that are typically driven by coronal mass ejections (CMEs) from the Sun. Here we conduct a case study of a type II radio burst that is associated with a C4.5-class flare and a blowout jet, but
Zhenyong Hou, Hui Tian, Wei Su, Maria S. Madjarska, Hechao Chen, Ruisheng Zheng, Xianyong Bai, Yuanyong Deng   +7 more
doaj   +1 more source

Variability of dB/dt in the African Sector During Solar Cycle 24—Implications for Geomagnetically Induced Currents

Space Weather, Volume 24, Issue 8, August 2026.
Abstract This paper quantitatively characterizes dB/dt peaks at four African equatorial‐ and low‐latitude stations, along latitudinal and local‐time gradients across different phases of selected geomagnetic storms. We investigate dB/dt response for intense geomagnetic storms, Dst ≤ −100 nT observed during solar cycle 24 over four stations in the ...
Wuraola E. Oyegunle, C. M. Ngwira, A. O. Akala, E. O. Oyeyemi, B. Olugbon, O. J. Oyedokun, P. O. Amaechi   +6 more
wiley   +1 more source

Variations of Heavy Ions in Interplanetary Shock Driven by Interplanetary Coronal Mass Ejections and Stream Interaction Regions

The Astrophysical Journal Supplement Series
In the solar wind, the fluctuation of heavy ion abundance serves as a crucial physical metric. This not only mirrors the attributes of the solar wind’s originating solar region but also signifies its influence on Earth’s magnetosphere.
Cong Wang, Qian Ye, Mu Li, Fei He, Xiaoxin Zhang   +4 more
doaj   +1 more source

Interplanetary Electric Fields for Extreme Magnetic Storms

Geophysical Research Letters, Volume 53, Issue 13, 16 July 2026.
Abstract Using a list of sudden‐commencement storms, the ring‐current index, and 1‐h near‐Earth solar‐wind measurements from solar cycles 20–25, we develop extreme‐value statistical models relating storm intensity D=max{−Dst} $D=\max \left\{-Dst\right\}$ to the storm main‐phase maximum duskward interplanetary electric field E $E$.
Jeffrey J. Love, E. Joshua Rigler, Ian G. Richardson, Kalevi Mursula   +3 more
wiley   +1 more source

Observations of the 2022 September 5 Solar Energetic Particle Event at 15 Solar Radii

The Astrophysical Journal
On 2022 September 5, Parker Solar Probe (Parker) observed a large solar energetic particle (SEP) event at the unprecedented distance of only 15 R _S from the Sun. The observations from the Integrated Science Investigation of the Sun (IS⊙IS) obtained over
C. M. S. Cohen, R. A. Leske, E. R. Christian, A. C. Cummings, G. A. de Nolfo, M. I. Desai, J. Giacalone, M. E. Hill, A. W. Labrador, D. J. McComas, R. L. McNutt Jr., R. A. Mewaldt, D. G. Mitchell, J. G. Mitchell, G. D. Muro, J. S. Rankin, N. A. Schwadron, T. Sharma, M. M. Shen, J. R. Szalay, M. E. Wiedenbeck, Z. G. Xu, O. Romeo, A. Vourlidas, S. D. Bale, M. Pulupa, J. C. Kasper, D. E. Larson, R. Livi, P. Whittlesey   +29 more
doaj   +1 more source

MMS Observations of the Energetic Particles Within Kelvin‐Helmholtz Waves at the Boundary of the 10 May 2024 Coronal Mass Ejection (CME)

Geophysical Research Letters, Volume 53, Issue 13, 16 July 2026.
Abstract On 10 May 2024, Earth was hit by a CME that drove the largest geomagnetic storm in 20 years. Multi‐spacecraft observations previously showed that the ∼100 nT north‐south IMF bz ${b}_{z}$ variation was driven by Kelvin‐Helmholtz waves with wavelength ∼250 RE ${R}_{E}$ and reconnection jets in the ±z $\pm z$‐direction (Nykyri, 2024a, https://doi.
Katariina Nykyri, Neetasha Arya, Scott Boardsen, Guan Le, Harri Laakso, Lynn Wilson, Xuanye Ma, Katherine Holland, Brandon Burkholder, Leon Ofman, Kyoung‐Joo Hwang, Dinesh Radhakrishnan, Shiva Kavosi, Daniel Gershman, Christine Gabrielse, Barbara Giles, Stephen Fuselier, Jim Burch   +17 more
wiley   +1 more source