Results 71 to 80 of about 600 (183)
Alfvén Waves from Interchange Reconnection at Separators as a Possible Source of Switchbacks
The Astrophysical JournalParker Solar Probe has observed Alfvénic fluctuations of amplitude large enough to occasionally reverse the local magnetic field direction—a phenomenon known as a switchback. Some have attributed switchbacks to reconnection in the low corona between open
Dana Longcope, Philip Klaassen
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Coronal holes and the solar polar field reversal [PDF]
Astronomy & Astrophysics, 2002 The relationship between the solar polar magnetic field reversal and coronal hole evolution is investigated for the time interval from 1996 to 2001. The distribution of coronal holes shows some evolutionary changes in relation to the polarity reversals, and these changes appear to be coordinated with changes in the global magnetic field structure ...
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Hydrostatic and dynamic models of solar coronal holes
The Astrophysical Journal, 1977 A description is presented of a sequence of one-dimensional fluid flow models of the transition zone and the inner corona. A hydrostatic model atmosphere in reasonable agreement with observations of closed, large-scale coronal structures found in the quiet sun is considered and various physical effects are introduced, one at a time, observing the ...
R. Rosner, G. S. Vaiana
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Solar coronal-hole plasma densities and temperatures [PDF]
Astronomy & Astrophysics, 2006 Polar plumes extending from the Sun into the solar corona have long been seen during eclipses, and can now be studied without this restriction with telescopes and spectrometers on board of spacecraft. Despite the large amount of observational data available on this prominent phenomenon, it is not clear whether plumes contribute substantially to the ...
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Journal of Space Weather and Space Climate, 2012 In past studies, we classified the near-Earth solar wind into three basic flow types based on inspection of solar wind plasma and magnetic field parameters in the OMNI database and additional data (e.g., geomagnetic indices, energetic particle, and ...
Richardson Ian G., Cane Hilary V.
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Discrete changes in solar coronal hole boundaries
The Astrophysical Journal, 1990 Sequences of Skylab X-ray images near central meridian passages of a large solar coronal hole are used here to examine hole boundary changes with a time resolution of 90 min. It is found that X-ray bright points play a key role in both the expansion and contraction of the coronal hole.
S. W. Kahler, D. Moses
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The Astrophysical Journal LettersWhile the amount of solar coronal energy flux leaving the “quiet” Sun, coronal holes, and active regions has been estimated by many, similar calculations for transients like coronal mass ejections (CMEs) based on observations are few. Using spectroscopic
R. Ramesh +5 more
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Solar Origins of Short-Term Periodicities in Near-Earth Solar Wind and Interplanetary Magnetic Field
Applied SciencesThis study investigates the solar origins of short-term periodicities in the near-Earth solar wind and interplanetary magnetic field (IMF) using long-term observations (1995–2024) and Potential Field Source Surface modeling.
Huichao Li +5 more
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Solar polar coronal hole - A mathematical simulation
The Astrophysical Journal, 1977 The northern polar region of the sun was studied during July 1973 by Munro and Jackson through use of the white-light coronagraph and the X-ray photographs produced by the Skylab mission. They described the northern polar hole as nearly axisymmetric and gave the geometry and density distribution under this approximation.
S. T. Suess +3 more
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