An animation of sunspot drawings by Galileo Galilei shows the eastward rotation of the Sun (North is toward the upper right corner of the diagrams). The animation shows the Sun on twenty-five consecutive days from June 5 through June 29, 1612. (PhotoShop/ImageReady animation by Courtney Seligman. See The Galileo Project for images of the Sun on these and other days in June and July of 1612.)
 The rotation of the Sun, demonstrated by the motion of sunspots. A composite "white-light" photo made over a number of days during August of 1999. (Louis Strous (LMSAL), SOHO - MDI Consortium, ESA, NASA, apod991021)
 A Dopplergram of the Sun showing the motion toward the Earth (darker colors on the left) and away from it (lighter colors on the right) due to its overall rotation. The maximum velocities are about one and a third miles per second or about five thousand miles per hour, which is about five times the rotational velocity at the Earth's equator. Since the Sun is 110 times the size of the Earth, the relatively low velocity means it takes a long time (almost a month) to rotate once. By subtracting the effects of the overall rotation of the Sun, Dopplergrams can also be used to study motions at the Solar surface, and provide the observational basis for helioseismology. (SOHO, ESA, NASA, SOI / MDI)
 How differential rotation winds up the Solar magnetic field. (Temporary image, borrowed from The Essential Cosmic Perspective, by Bennett et al.)
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