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Rotation anomaly of the Sun
Author(s) -
Kotov Valery A.
Publication year - 2020
Publication title -
astronomische nachrichten
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.394
H-Index - 63
eISSN - 1521-3994
pISSN - 0004-6337
DOI - 10.1002/asna.202013625
Subject(s) - sidereal time , equator , anomaly (physics) , physics , earth's rotation , rotation (mathematics) , solar rotation , astrophysics , geophysics , geodesy , astronomy , atmospheric sciences , geology , latitude , solar physics , condensed matter physics , mathematics , geometry
Does the Sun always rotate correctly? On the basis of the measurements of its mean magnetic field (more than 27 thousand daily values, obtained by seven observatories during 1968–2018) and resonance relations of the solar system, the sidereal spin period of the Sun as a star is determined as 25.165(6) days and that of the solar equator as 25.081(7) days. After 1993, however, a remarkable violation of the solar equatorial rate, through an unknown cause, has happened: the spin coherency of the mean field disintegrated and made way for nearly chaotic variations with quasi‐periods of 24.7–25.4 days. The phenomenon is thought to be tied to anomaly of the Wolf cycles 23 and 24, accompanied presumably by a global change of the Earth's climate (with unclear mechanism of the Sun–Earth influence).