Results 11 to 20 of about 1,446 (180)

Coronal Holes and the Solar Wind [PDF]

Highlights of Astronomy, 1992
Around the turn of the century Professor Kristian Birkeland at the University of Kristiania (Oslo) carried out laboratory studies of the emission of charged particles from the Sun and their interaction with comets and magnetized planets. He found that cathode rays emitted by a magnetized sphere are bent toward the equator along trajectories similar to ...
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Statistics of counter-streaming solar wind suprathermal electrons at solar minimum : STEREO observations [PDF]

, 2010
Previous work has shown that solar wind suprathermal electrons can display a number of features in terms of their anisotropy. Of importance is the occurrence of counter-streaming electron patterns, i.e., with "beams" both parallel and anti-parallel to ...
Skoug, R. M., C. Mazelle, A. Opitz, Luhmann, J.G., E. Penou, Penou, E., C. Jacquey, Génot, Vincent, Larson, D. E., Jian, L., Sauvaud, J.-A., Fedorov, A., Jacquey, C.J., P. Schroeder, Gosling, J.T., Skoug, R.M., R. M. Skoug, Jacquey, C., K. D. Simunac, Meziane, K., Russell, C. T., Lavraud, B., C. Foullon, Foullon, C., J.-A. Sauvaud, Sauvaud, Jean-André, Rouillard, A.P., I. Dandouras, Rouillard, A. P., Génot, V., Luhmann, J. G., J. T. Gosling, C. T. Russell, J. T. Steinberg, Foullon, C. (Claire), A. B. Galvin, Opitz, A., Simunac, K. D., Larson, D.E., K. Meziane, Mazelle, C., Foullon, Claire, A. Fedorov, Galvin, A. B., J. G. Luhmann, Sauvaud, J.A., P. Louarn, Russell, C. T. (Christopher T.), Steinberg, John Tyree, D. E. Larson, Dandouras, I., Steinberg, J. T., Simunac, K.D.C., A. P. Rouillard, Schroeder, P., Russell, C.T., Galvin, A.B., Steinberg, J.T., Gosling, J. T., L. Jian, Louarn, P., V. Génot, B. Lavraud   +62 more
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Solar Wind Forecasting with Coronal Holes [PDF]

Solar Physics, 2006
An empirical model for forecasting solar wind speed related geomagnetic events is presented here. The model is based on the estimated location and size of solar coronal holes. This method differs from models that are based on photospheric magnetograms (e.g., Wang-Sheeley model) to estimate the open field line configuration.
Robbins, S., Henney, C. J., Harvey, J. W.   +2 more
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Coronal Holes [PDF]

, 2016
Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed solar wind ...
Cranmer, Steven
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Relationship of Coronal Mass Ejection Events with Solar Flares and coronal Holes [PDF]

Symposium - International Astronomical Union, 1990
We present an analysis of the relationship between coronal mass ejection (CME) events with solar flares and coronal holes. Out of 79 CME events whose location and span are known, 10 CME event circles contain solar flares. On the other hand out of 71 CME events (selected for the study with coronal holes) 40 CME event circles contain coronal holes.
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Automatic detection of limb prominences in 304 A EUV images [PDF]

, 2010
A new algorithm for automatic detection of prominences on the solar limb in 304 A EUV images is presented, and results of its application to SOHO/EIT data discussed.
Labrosse, N., Dalla, S., Marshall, S.
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Geomagnetic storms forecasting from solar coronal holes

Monthly Notices of the Royal Astronomical Society, 2022
<p>Coronal holes (CHs) are the source of high-speed solar wind streams (HSSs), which interact with the slow solar wind and form corotating interaction regions (CIRs) in the heliosphere. These high-speed streams and their associated structures influence the geomagnetic activity, causing recurrent geomagnetic storms. The propagation time of
Simona Nitti, Tatiana Podladchikova, Astrid M. M. Veronig, Stefan Hofmeister, Giuliana Verbanac, Mario Bandić   +5 more
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Investigating Alfvénic wave propagation in coronal open-field regions

, 2015
The physical mechanisms behind accelerating solar and stellar winds are a long-standing astrophysical mystery, although recent breakthroughs have come from models invoking the turbulent dissipation of Alfvén waves.
Morton, Richard, Tomczyk, Steve, Pinto, Rui   +2 more
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Active Region Modulation of Coronal Hole Solar Wind [PDF]

The Astrophysical Journal, 2019
Abstract Active regions (ARs) are a candidate source of the slow solar wind (SW), the origins of which are a topic of ongoing research. We present a case study that examines the processes by which SW is modulated in the presence of an AR in the vicinity of the SW source.
Allan R. Macneil, Christopher J. Owen, Deborah Baker, David H. Brooks, Louise K. Harra, David M. Long, Robert T. Wicks   +6 more
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Identifying and Predicting Coronal Mass Ejection Occurrence: Observational Checklists for Space Weather Forecasters

Space Weather, Volume 24, Issue 6, June 2026.
Abstract Ejections of magnetized plasma from the Sun, known as coronal mass ejections, can drive major geomagnetic activity if Earth‐directed, and are therefore monitored by space weather forecasters. The current focus being the forecast of the arrival time of a coronal mass ejection at Earth and the level of geomagnetic impact.
L. M. Green, A. W. James, N. Ngampoopun, S. L. Yardley, K. Waite, E. K. Mottram, J. Hernandez Camero, J. O'kane   +7 more
wiley   +1 more source