Results 31 to 40 of about 1,036 (175)

Automated Mineral Identification and Rock‐Type Classification of Lunar Mare Basalts Using SEM Images

Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 4, August 2026.
Abstract We present an automated system for identifying minerals and classifying rock types in Apollo lunar mare basalts using scanning electron microscopy (SEM) imagery. Mineral segmentation is based on a U‐Net architecture, supplemented by two scale‐aware models designed to incorporate pixel size information.
Ji‐In Jung, Sonia M. Tikoo, Jaehong Chung, Claire I. O. Nichols   +3 more
wiley   +1 more source

Solar and stellar dynamos – latest developments [PDF]

Astronomische Nachrichten, 2002
6 pages, 4 figures, Astron Nachr (accepted; proceedings of "1st Potsdam Thinkshop on Sunspots and Starspots", Potsdam, Germany, May 2002)
Brandenburg, Albrecht, Dobler, Wolfgang
openaire   +3 more sources

Massive Rocky Planets May Suppress Deep Melting

AGU Advances, Volume 7, Issue 4, August 2026.
Abstract Melting properties of silicates are critical to understanding the thermal evolution of rocky planetary interiors. In the deep mantles of massive rocky planets, post‐post‐spinel Mg2SiO4 ${\text{Mg}}_{2}{\text{SiO}}_{4}$ is potentially one of the most abundant mineral phases, yet its melting behavior remains unconstrained. Here, we determine the
Donghao Zheng, Yihang Peng, Jie Deng
wiley   +1 more source

Understanding mechanisms underlying solar cycle predictability with a general framework

Astronomy & Astrophysics
Context. The large-scale magnetic field observed at the solar surface is produced by the interior dynamo process. Whether this surface field also provides the dominant seed for the subsequent dynamo cycle, however, remains controversial, with important ...
Li Binghang, Jiang Jie, Luo Yukun
doaj   +1 more source

Multimode Representation of the Magnetic Field for the Analysis of the Nonlinear Behavior of Solar Activity as a Driver of Space Weather

Mathematics, 2022
Estimating and predicting space weather is important to the space industry and space missions. The driver of space weather, especially near the Earth, is solar activity, the study of which is an important task.
Elena Popova, Anatoli I. Popov, Roald Sagdeev   +2 more
doaj   +1 more source

A Contrasting TEC Behavior Over the Low‐Latitude Post‐Midnight Sector During Recovery Phases of May and October 2024 Storms: Possible Role of PPEF, DDEF, and O/N2

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract The present study reports on the variability of the post‐midnight ionosphere over the low‐latitude sector during the recovery phases of the May and October 2024 storms. Multi‐instrument observations, comprising global navigation satellite system total electron content (TEC), F‐layer peak height, electron density profiles, and column O/N2 ...
Rahul Rathi, Akash Kumar, Alok Kumar Ranjan, Dipjyoti Patgiri, Satarupa Chakrabarti, Lot Ram   +5 more
wiley   +1 more source

The Solar Dynamo [PDF]

International Astronomical Union Colloquium, 1990
AbstractThe phenomena of solar activity are connected with a general magnetic field of-the Sun which is due to a dynamo process essentially determined by the α-effect and the differential rotation in the convection zone. A few observational facts are summarized which are important for modelling this process.
openaire   +1 more source

Longitudinal Variation of Ionospheric Irregularities and Response of the Ionosphere During 10–13 May and 10–13 October 2024 Geomagnetic Storms

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract We examine the response of the ionosphere to the 10–13 May 2024 and 10–13 October 2024 geomagnetic storms, the two recent great geomagnetic storms of solar cycle 25. We identified the occurrence of ionospheric irregularities during the two geomagnetic storms.
Valence Habyarimana, Mark B. Moldwin, John Bosco Habarulema, Sharon Aol, Jean Claude Uwamahoro, Teshome Dugassa, Daniel Okoh, Solomon Otoo Lomotey   +7 more
wiley   +1 more source

The Solar Dynamo [PDF]

Symposium - International Astronomical Union, 1993
The generation of the solar magnetic field is generally ascribed to dynamo processes in the convection zone. The dynamo effects, differential rotation (ω–effect) and helical turbulence (α–effect) are explained, and the basic properties of the mean–field dynamo equations are discussed in close comparison with the observed solar cycle.Especially the ...
openaire   +1 more source

Currents in the Martian Ionosphere: Cases Without Strong Crustal Magnetic Fields

Journal of Geophysical Research: Planets, Volume 131, Issue 8, August 2026.
Abstract The Martian ionosphere hosts complex current systems driven both by solar wind interactions and neutral wind dynamo processes. While the global patterns of these current systems have been statistically examined, their detailed structures and orientations remain poorly constrained.
JunFeng Qin, Shannon Curry, Wenyi Sun, Matthew Fillingim, Robert Lillis, Yingjuan Ma, Yaxue Dong, Robin Ramstad, Shaosui Xu, Dave Mitchell   +9 more
wiley   +1 more source