Results 41 to 50 of about 1,774 (127)
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
Measuring helium abundance difference in giants of NGC 2808 [PDF]
, 2011 Multiple populations have been detected in several globular clusters (GC) that do not display a spread in metallicity. Unusual features of their CMD can be interpreted in terms of differences in the Helium content of the stars belonging to the sub ...
Cacciari, C. +3 more
core +2 more sources
The Magnetic Field Configuration in Solar and Stellar Chromospheres [PDF]
Symposium - International Astronomical Union, 1983 Calculations are presented for the inhomogeneous magnetic field structure above a stellar photosphere which has magnetic flux tubes located at the downdraughts of its supergranulation pattern. Regions can be delineated where the ambient magnetic energy density is large or small compared with the thermal energy density derived from a model atmosphere ...
U. Anzer, D. J. Galloway
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
Heating of Stellar Chromospheres and Transition Regions [PDF]
Symposium - International Astronomical Union, 2004 To explain the heating of stellar chromospheres and transition regions, two classes of heating mechanisms have been considered: dissipation of acoustic and magnetic waves generated in stellar convection zones; and dissipation of currents generated by photospheric motions of surface magnetic fields.
openaire +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
Ca II H and K Chromospheric Emission Lines in Late K and M Dwarfs
, 2006 We have measured the profiles of the Ca II H and K chromospheric emission lines in 147 main sequence stars of spectral type M5-K7 (0.30-0.55 solar masses) using multiple high resolution spectra obtained during six years with the HIRES spectrometer on the
Doyle J. G. +7 more
core +1 more source
Quasi‐Periodic Pulsations in Ionospheric TEC Synchronized With Solar Flare EUV Emission
Journal of Geophysical Research: Space Physics, Volume 130, Issue 4, April 2025.Abstract The extreme ultraviolet (EUV) and X‐ray radiation emitted during solar flares has been shown to significantly increase the electron density of the Earth's ionosphere. During flares, quasi‐periodic pulsations in X‐ray flux originating in the corona have previously been linked to subsequent pulsations in the Earth's ionospheric D‐region. Similar
Aisling N. O’Hare +3 more
wiley +1 more source
Developments in the understanding and use of chromospheric diagnostics are discussed with emphasis on the following aspects: (1) trends emerging from semiempirical models of single stars; (2) the validity of claims that theoretical models of ...
Linsky, J. L.
core +1 more source
Multi‐Source Forecast of Solar Cycle Flare Activity Using the Novel Informer‐Based Models
Space Weather, Volume 23, Issue 4, April 2025.Abstract Solar flares, the significant indicators of solar activity, have an impact on Earth's satellites and communication systems. Accurate prediction of solar flare events is crucial for mitigating these effects. In this work, we use multiple data sources, including Geostationary Operational Environmental Satellites soft X‐ray flare flux and the ...
Jie Cao +11 more
wiley +1 more source