POLAR FLOWS IMAGE: This image is a graphical representation of the surface flow from the equator to the poles of the Sun. The flow lines overlay an image of the rotation speed at the Sun’s surface, taken using the Michelson Doppler Imager (MDI) instrument on the NASA/ESA Solar and Heliospheric Observatory (SOHO) spacecraft over a period of 12 months ending June 1997. The false colors represent speed; red material is rotating faster than the blue material. As this material rotates, it is also flowing toward the poles at a relatively slow velocity of about 50 miles per hour. The lines represent how this motion would appear if you could stand on the surface of the Sun about 30 degrees from the equator, and move with the same speed as the material there. If you were at this position in the northern hemisphere, material closer to the equator would appear to move to the right of the image as it flowed north, because it is rotating faster. Material closer to the north pole would appear to move to the left as it flowed north, because it is rotating slower. The cutaway on the left of the image represents the observed polar flow 15 thousand miles beneath the surface and a hypothetical, slower moving return flow from the poles to the equator, estimated to be 120 thousand miles beneath the surface. (Photo Credit: Stanford University)

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