Results 11 to 20 of about 546 (232)
Meridional motions of sunspots and sunspot groups
The Astrophysical Journal, 1986 Etude des positions des taches solaires et des groupes de taches determinees au Mont Wilson en lumiere blanche entre 1917 et 1983, afin d'examiner la nature des mouvements meridiens des taches et groupes durant cet ...
R. Howard, P. A. Gilman
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PRE-FLARE DYNAMICS OF SUNSPOT GROUPS [PDF]
The Astrophysical Journal, 2014 Several papers provide evidences that the most probable sites of flare onset are the regions of high horizontal magnetic field gradients in solar active regions. Besides the localization of flare producing areas the present work intends to reveal the characteristic temporal variations in these regions prior to flares.
Korsós, Marianna Brigitta +2 more
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Research on Mount Wilson Magnetic Classification Based on Deep Learning
Advances in Astronomy, 2021 The Mount Wilson magnetic classification of sunspot groups is thought to be meaningful to forecast flares’ eruptions. In this paper, we adopt a deep learning method, CornerNet-Saccade, to perform the Mount Wilson magnetic classification of sunspot groups.
Yuanbo He +5 more
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On the size distribution of sunspot groups in the Greenwich sunspot record 1874–1976 [PDF]
Astronomy & Astrophysics, 2005 accepted by A& ...
Baumann, I., Solanki, S.
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The Development of Sunspot Groups [PDF]
International Astronomical Union Colloquium, 1993 AbstractIt is shown that the growth and decay rates of sunspot groups are both a function of the axial tilt angles of the groups. Both of these rates reach a maximum near the average tilt angle, which is around +5°, not 0°. (A positive tilt angle represents the situation where the leading spots are equatorward of the following spots).
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Solar-Terrestrial Physics, 2016 This paper considers a longitude distribution of sunspot groups over 1982–2013, using data from the National Geophysical Data Center (Boulder, USA).
Rybak A.L.
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Journal of Water and Climate Change, 2021 The relation between sunspots and rainfall patterns is still obscure in Africa, especially for Sudan and South Sudan. This research explores the response of rainfall to solar activity in eastern regions of Africa, with a case study in Sudan and South ...
Mostafa A. Mohamed +1 more
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Evolutionary Relationship between Sunspot Groups and Soft X-Ray Flares over Solar Cycles 21–25
The Astrophysical Journal, 2023 Studying the interaction between solar flares and sunspot groups (SGs) is crucial for understanding and predicting solar activity. We examined the distribution, correlation, and flaring rates in the northern and southern hemispheres to reveal the ...
Jiaqi Lin +5 more
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Solar activity cycle 25: the first three years
Solar-Terrestrial Physics, 2023 We analyze features of current solar activity cycle 25 for the first three years of its development (2020–2022). Compared to cycle 24, the current cycle is shown to exceed the previous one in the number of sunspot groups (1.5 times), the number of flares
Yazev S. A. +2 more
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A Recount of Sunspot Groups on Staudach’s Drawings [PDF]
Solar Physics, 2016 We have examined the more than 1100 drawings of the solar disk made by the German astronomy amateur Johann Caspar Staudach during 1749-1799 and counted the spots on each image. Using the modern perception of how to group spots into active regions we regrouped the spots as a modern observer would.
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