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Positions of sunspot groups and solar rotation

✍ Scribed by Jaakko Tuominen; Juhani Kyrölsainen

Publisher
Springer
Year
1981
Tongue
English
Weight
503 KB
Volume
74
Category
Article
ISSN
0038-0938

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✦ Synopsis

The question is studied whether the one-year solar oscillation found by V. F. Chistyakov for the years 1965-1973 can be traced in the observations of sunspots of 1874-1971 published by Greenwich Observatory. The result is negative. But the study leads to the following two conclusions: (1) The average observable centres of gravity of spot groups are variably displaced towards the central meridian or towards the limb, the time scale of this variability being of the order of 70 years. Thus the angular velocity should be determined from recurrent groups in transit of the central meridian only. (2) The angular velocity will be smaller when determined from older spots. * Proceedings of the 14th ESLAB Symposium on Physics of Solar Variations, 16-

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