Results 41 to 50 of about 318 (133)
Journal of Geophysical Research: Machine Learning and Computation, Volume 2, Issue 3, September 2025.Abstract Recently, many machine learning‐based models have been developed to predict geomagnetic activity several days in advance directly from space‐borne solar imaging. To better understand and improve these models, we compare dimensionality reduction techniques to extract abstract features from solar images for space weather‐related downstream tasks.
Maria Tahtouh +5 more
wiley +1 more source
Deriving the Coronal Separatrix‐Web With the WSA Model
Journal of Geophysical Research: Space Physics, Volume 130, Issue 8, August 2025.Abstract We demonstrate a new capability of the Wang‐Sheeley‐Arge (WSA) model to routinely derive the coronal separatrix web (S‐web) as a standard data product. We describe our methodology for deriving the squashing factor (Q $Q$) and we use Carrington rotation (CR) 2109 to illustrate the validation of our output with that derived from the POT3D model.
Samantha Wallace +5 more
wiley +1 more source
Journal of Geophysical Research: Space Physics, Volume 130, Issue 8, August 2025.Abstract Working toward the goal of understanding solar wind (SW) entry to the Earth's magnetosphere, this study examines solar‐origin ion composition in the magnetotail. During its trajectory, Wind spent a significant amount of time in the Earth's magnetotail, where its SupraThermal Ion Composition Spectrometer (STICS) measured the mass and mass per ...
S. Colón‐Rodríguez +3 more
wiley +1 more source
Chromospheric activity to age relationship among Sun-like stars
, 2021 {"references": ["Adibekyan, V. Zh., Sousa, S. G., Santos, N. C. et al. 2012, \\aap, 545, A32", "Affer, L., Micela, G., Favata, F. et al. 2013, \\mnras, 430, 1433", "Barnes, S. A. 2003, \\apj, 586, 464", "Barnes, S. A., Weingrill, J., Fritzweski, D., et al. 2016, \\apj, 823, 16", "Booth, R. S., Poppenhaeger, K., Watson, C. A. et al.
openaire +1 more source
Ultraviolet Oscillations in the Chromosphere of the Quiet Sun
The Astrophysical Journal, 2004 Quiet-Sun oscillations in the four Transition Region and Coronal Explorer (TRACE) ultraviolet passbands centered on 1700, 1600, 1216, and 1550 A are studied using a wavelet-based technique. Both network and internetwork regions show oscillations with a variety of periods and lifetimes in all passbands. The most frequent network oscillation has a period
Keenan, Francis +5 more
openaire +1 more source
Slow Solar Wind: Origin in an Independent Small‐Scale Solar Dynamo
Geophysical Research Letters, Volume 52, Issue 13, 16 July 2025.Abstract Separation of the solar wind (SW) into three flow types (coronal mass ejections (CMEs), high speed streams (HSSs), and slow solar wind (SSW)) reveals an inverse relationship between the percentage of time Earth spends in SSW during a year and its annually averaged magnetic field strength (B).
E. W. Cliver +2 more
wiley +1 more source
NOAA's National Centers for Environmental Information Space Weather Data Inventory Status
Space Weather, Volume 23, Issue 7, July 2025.Abstract We present here an updated overview of the Space Weather data curated and/or generated, improved, archived, and disseminated by the Solar Terrestrial Physics (STP) Section of the National Centers for Environmental Information (NCEI) in the National Oceanic and Atmospheric Administration (NOAA).
Alessandra Abe Pacini +2 more
wiley +1 more source
Robust Statistical Techniques for Operational Maintenance of the 10.7 cm Solar Radio Flux
Space Weather, Volume 23, Issue 5, May 2025.Abstract The F10.7 solar radio flux is a critical quantity for operational space weather nowcasting and forecasting, where it is routinely used as a driver for coupled atmospheric models to estimate a variety of important quantities such as the neutral atmospheric density.
Daniel A. Brandt +2 more
wiley +1 more source
Chromospheres, Coronae, and Mass Loss in Stars Hotter than the Sun [PDF]
Highlights of Astronomy, 1980 AbstractReviews of the mass-loss characteristics of OB stars have been published recently, and the present review therefore emphasizes the A and F stars and very recent results on O and B stars. For the F stars, chromospheric indicators are present in the form of emission lines, seen in visible and ultraviolet wavelengths.
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Dynamic models of the sun from the convection zone to the chromosphere [PDF]
Proceedings of the International Astronomical Union, 2006 AbstractThe chromosphere in internetwork regions of the quiet Sun was regarded as a static and homogeneous layer for a long time. Thanks to advances in observations and numerical modelling, the wave nature of these atmospheric regions received increasing attention during the last decade.
openaire +2 more sources