Results 61 to 70 of about 1,735 (184)

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

The Evolution of Photospheric Magnetic Fields at the Footpoints of Reconnected Structures in the Solar Atmosphere

The Astrophysical Journal
Magnetic reconnection is believed to play an important role in the release and conversion of energy among magnetized plasma systems. So far, we have been unable to understand under what conditions magnetic reconnection can take place.
Tao Ding, Jun Zhang, Yue Fang, Junchao Hong, Yi Bi, Yongyuan Xiang   +5 more
doaj   +1 more source

First Report of Rising‐Tone EMIC Waves Driven by the Magnetosheath High‐Speed Jet

Geophysical Research Letters, Volume 53, Issue 14, 28 July 2026.
Abstract Magnetosheath high‐speed jets (HSJs) are pervasive transient structures with enhanced dynamic pressure in the terrestrial magnetosheath and can exert notable local impacts on the magnetopause. Although various geoeffects have been reported to be associated with HSJs, whether HSJs can drive the generation of electromagnetic ion cyclotron (EMIC)
Wentian Lei, Xinliang Gao, Xuan Zhou, Jiuqi Ma, Tong Shao, Yuxiang Wang, Quanming Lu   +6 more
wiley   +1 more source

Magnetic Reconnection–driven Energization of Protons up to ∼400 keV at the Near-Sun Heliospheric Current Sheet

The Astrophysical Journal Letters
We report observations of direct evidence of energetic protons being accelerated above ∼400 keV within the reconnection exhaust of a heliospheric current sheet (HCS) crossing by NASA’s Parker Solar Probe (PSP) at a distance of ∼16.25 solar radii ( R _s )
M. I. Desai, J. F. Drake, T. Phan, Z. Yin, M. Swisdak, D. J. McComas, S. D. Bale, A. Rahmati, D. Larson, W. H. Matthaeus, M. A. Dayeh, M. J. Starkey, N. E. Raouafi, D. G. Mitchell, C. M. S. Cohen, J. R. Szalay, J. Giacalone, M. E. Hill, E. R. Christian, N. A. Schwadron, R. L. McNutt Jr., O. Malandraki, P. Whittlesey, R. Livi, J. C. Kasper   +24 more
doaj   +1 more source

Enhancement of Dayside Westward Electrojet: Triggering Conditions and Current Closures

Geophysical Research Letters, Volume 53, Issue 14, 28 July 2026.
Abstract Geomagnetic substorms are a major path for energy storage and release in the magnetosphere, which typically occur in the midnight sector with a strong enhancement of westward electrojets. However, by analyzing 37,940 events from a substorm list, about 3% of events unexpectedly initiated in the noon sector.
Haobo Fu, Chao Yue, Dedong Wang, Qiugang Zong, Huiting Feng, Yuri Shprits   +5 more
wiley   +1 more source

Three Types of Solar Coronal Rain during Magnetic Reconnection between Open and Closed Magnetic Structures

The Astrophysical Journal
Coronal rain (CR) is a crucial part of the mass cycle between the corona and chromosphere. It includes flare-driven CR and two types of quiescent CR, along nonflaring active region closed loops and along open structures, separately, labeled as type I ...
Fangfang Qiao, Leping Li, Hui Tian, Zhenyong Hou, Hongqiang Song, Kaifan Ji, Zheng Sun   +6 more
doaj   +1 more source

TRACERS Small‐Scale Field‐Aligned Currents and Intense GPS Amplitude and Phase Scintillations in the Nightside Auroral Region

Geophysical Research Letters, Volume 53, Issue 14, 28 July 2026.
Abstract We present conjugate observations of ionospheric small‐scale magnetic perturbations (dB) $(dB)$ and GPS scintillations from the Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) and the Canadian High Arctic Ionospheric Network (CHAIN) during a storm‐time substorm on 9 August 2025 in the nightside auroral region ...
Yangyang Shen, Robert J. Strangeway, Hao Cao, James M. Weygand, Jiashu Wu, Anthony McCaffrey, P. T. Jayachandran, Daniel Billett, Magnus F. Ivarsen, Christopher Watson, Sheng Tian, Marit Oieroset, David Miles   +12 more
wiley   +1 more source

Local Evolution of a Prenoon Drainage Plume

Geophysical Research Letters, Volume 53, Issue 13, 16 July 2026.
Abstract Plasmaspheric drainage plumes are typically observed in the postnoon sector during geomagnetic storms, but their local evolution in the prenoon sector remains poorly understood. Here, we report in situ observations from the Van Allen Probe, revealing multiple localized enhancements in cold electron density near apogee in the prenoon sector ...
Suk‐Bin Kang, Mei‐Ching Fok, Cristian Ferradas, Alex Glocer, Megha Pandya, J. D. Huba   +5 more
wiley   +1 more source

Martian Magnetotail Neutral Sheet Asymmetry Driven by Heavy Planetary Pickup Ions

Geophysical Research Letters, Volume 53, Issue 13, 16 July 2026.
Abstract In the induced magnetotail of Mars, the neutral sheet is an important channel for atmospheric ion escape, yet the role of heavy planetary pickup ions in shaping its geometry has been unclear. Using three‐dimensional hybrid simulations, we demonstrate that these ions induce a global neutral sheet asymmetry via mass loading.
Jingyi Zhou, Zhenpeng Su, Kaijun Liu, Rentong Lin, Esa Kallio, Riku Jarvinen, Yuming Wang   +6 more
wiley   +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