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Solar 'hot spots' are still hotLongitude distributions of solar flares are not random but show evidence for active zones (or hot spots) where flares are concentrated. According to a previous study, two hot spots in the northern hemisphere, which rotate with a synodic period of about 26.72 days, produced the majority of major flares, during solar cycles 20 and 21. The more prominent of these two hot spots is found to be still active during the rising part of cycle 22, producing the majority of northern hemisphere major flares. The synodic rotation period of this hot spot is 26.727 + or - 0.007 days. There is also evidence for hot spots in the southern hemisphere. Two hot spots separated by 180 deg are found to rotate with a period of 29.407 days, with one of them having persisted in the same locations during cycles 19-22 and the other, during cycles 20-22.
Document ID
Document Type
Reprint (Version printed in journal)
External Source(s)
Bai, Taeil
(Stanford University CA, United States)
Date Acquired
August 15, 2013
Publication Date
November 20, 1990
Publication Information
Publication: Astrophysical Journal, Part 2 - Letters
Volume: 364
ISSN: 0004-637X
Subject Category
Solar Physics
Accession Number
Funding Number(s)
CONTRACT_GRANT: N00014-89-J-1024
CONTRACT_GRANT: N00014-85-K-0111
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