Abstract
One of the most outstanding feature of solar activity in the decade 1959–1969 was a very strong asymmetry on the two hemispheres. On the northern hemisphere spots, faculae and prominences were more numerous and the white light corona was brighter than on the southern hemisphere. This happened as well in the main zone as in the polar zone. The green coronal line too was brighter on the northern hemisphere, but the intensity of the red line was asymmetric in the opposite sense. From this behaviour it follows that over the more active hemisphere the corona is denser and hotter. Between density N e and temperature T holds the relation: N e = 10−10 T 3. The real asymmetry was strengthened by a phase difference of the two hemispheres. This phase shift is subject to a long period that contains 8 eleven-year cycles. The intensity of the individual cycles follows the same long period. With low maxima of solar activity the northern hemisphere precedes, with high maxima the southern hemisphere (Figure 3).
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
Refereaces
Billings, D. E.: 1966, A Guide to the Solar Corona, Academic Press, New York, p. 240.
Burgess, A. and Seaton, M.: 1964, Monthly Notices Roy. Astron. Soc. 127, 355.
Reimers, D.: 1971, Astron. Astrophys. 10, 182.
Waldmeier, M.: 1939, Astron. Mitt. Zürich, No. 138, 470.
Waldmeier, M.: 1957, Z. Astrophys. 43, 149.
Waldmeier, M.: 1958–1971, Astron. Mitt. Zürich, Nos. 215, 221, 229, 237, 244, 251, 261, 267, 273, 279, 283, 288, 296, 303.
Waldmeier, M.: 1962–1969, Astron. Mitt. Zürich, Nos. 245, 255, 263, 269, 280, 293.
Waldmeier, M.: 1967, Observatory, 87, 82.
Waldmeier, M.: 1971, Physics of the Solar Corona, Reidel Publ. Co., Dordrecht-Holland, p. 130.
Author information
Authors and Affiliations
Additional information
Astronomische Mitteilungen der Eidgenössischen Sternwarte Zürich, No. 302.
Rights and permissions
About this article
Cite this article
Waldmeier, M. The asymmetry of solar activity in the years 1959–1969. Sol Phys 20, 332–344 (1971). https://doi.org/10.1007/BF00159763
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00159763