Results 251 to 260 of about 95,125 (291)

Differential solar rotation depends on solar activity

Nature, 1979
SUNSPOTS have long been used as tracers to determine the rotation rate of the Sun. Scheiner1 noted 250 years ago that low-latitude sunspots rotate more rapidly than those at high latitude (‘differential rotation’). In a recent review, Howard2 stressed the limitations of the sunspot technique for determining rotation rate and differential rotation, as ...
D. H. CLARK, B. D. YALLOP, S. RICHARD, B. EMERSON, P. J. RUDD   +4 more
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The Differential Solar Rotation

1994
Theory and observations of the solar differential rotation are reviewed, concentrating on recent developments. Reynolds stresses produced by stratified rotating turbulence have recently become available as fully nonlinear functions of the angular velocity. A model based on this theory has reproduced the solar rotation; almost no tuning of the theory to
Günther Rüdiger, Leonid L. Kitchatinov
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Solar radiation and solar differential rotation

Solar Physics, 1988
Areas of sunspots and their positions taken from the Greenwich Photoheliographic Results (1874–1976) and typical intensities of the umbrae and penumbrae are used to calculate daily values of the solar flux at a wavelength of about 500 nm. Using overlapping time series of 512 days each solar rotation periods are determined by Fourier transformation. The
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Differential rotation of solar filaments

Solar Physics, 1974
The latitudinal component of solar differential rotation and the possibility of a radial component are discussed and compared to the observed rotational velocities of solar filaments. The author's values of rotational rate versus heliographic latitude for 100 points in the solar atmosphere derived from 17 quiescent filaments are shown to be comparable
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Models of solar differential rotation

Geophysical & Astrophysical Fluid Dynamics, 1982
Abstract Models of a differentially rotating compressible convection zone are calculated, considering the inertial forces in the poloidal components of the equations of motion. Two driving mechanisms have been considered: latitude dependent heat transport and anisotropic viscosity.
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Differential Rotation and the Solar Oblateness

Nature, 1967
A few weeks ago, Dr I. W. Roxburgh questioned an earlier argument by Professor R. H. Dicke that the observed flattening of the Sun would account for part of the rotation of the orbit of Mercury otherwise attributable to general relativity. Roxburgh advanced arguments which suggest that the surface of the Sun may not be an equipotential surface, largely
R. H. DICKE, H. MARK GOLDENBERG
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Differential rotation of solar magnetic fields

Bulletin of the Crimean Astrophysical Observatory, 2008
The connection of the differential rotation of solar magnetic fields with the field sign and strength is studied. The synoptic maps of magnetic fields over the last three solar cycles taken at the Kitt Peak Observatory served as input data for the study.
O. A. Andreyeva, Ya. I. Zyelyk, N. N. Stepanian   +2 more
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A model of solar differential rotation

Solar Physics, 1991
An axisymmetric model for the Sun's differential rotation based upon a mechanism for angular momentum transport by compressible convection is developed. Convective heat transport is also considered. The model is simplified by the neglect of meridional circulation and radiative heat transport but is otherwise a self-consistent one because no adjustable ...
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Differential rotation of the solar electron corona

Solar Physics, 1969
Autocorrelation analyses of K-coronameter observations made at Haleakala and Mauna Loa, Hawaii, during 1964–1967 have established average yearly rotation rates of coronal features as a function of latitude and height above the limb. At low latitudes the corona was found to rotate at the same rate as sunspots but at higher latitudes was consistently ...
Richard T. Hansen, Shirley F. Hansen, Harold G. Loomis   +2 more
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Solar differential rotation derived from sunspot observations

Solar Physics, 1990
Sunspot drawings obtained at National Astronomical Observatory of Japan during the years 1954–1986 were used to determine the differential rotation of the Sun. From the limited data set of three solar cycles it was found that three factors (the level of cycle activity, the cycle phase, and sunspot type) affect the solar rotation rate.
Maspul Aini Kambry, Jun Nishikawa
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