Posted on 06/02/2007 8:28:43 PM PDT by SunkenCiv
The first-ever star surface map reveals a rapidly rotating giant orb with hot poles and a cooler, thickened equator that is radically different from our sun... "Because we have the highest resolution in the world, we are able to image a star a million times farther away than the sun," said John Monnier of the University of Michigan in Ann Arbor. He and several colleagues have published their map of Altair in the May 31 issue of Science Express. The image of Altair appears to defy the current, rather simple, models of how stars work, says Monnier. Those models had predicted that the star would have higher temperatures at the poles and somewhat lower temperatures around its inflated, fast-moving equator. But the real Altair shows an even darker, cooler equator than expected. "(The models) don't fit," Monnier told Discovery News. "They assume a solid body." In other words, the models assume that the equator moves in sync with the poles, which may not be the case on such a large, hot star that's rotating much faster than our sun.
(Excerpt) Read more at dsc.discovery.com ...
A map of the fast-spinning star, Altair, was made by collecting near-infrared light from four separate telescopes. The map reveals a rapidly rotating giant orb very different from our own sun, with hot poles and a cooler, thickened equator. [John Monnier/University of Michigan]
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Why would they assume a solid body? It is well known that the rotational period of the solar polar regions does not match the equator. That’s why we get sunspots — the magnetic field lines twist and tear due to differential rotation.
Of course, if the star is “squashed” with a “distended” equator, then of course the poles are warmer — they are closer to the nuclear core that powers the star.
Never fear, Captain Kirk and his crew will sort it out in a few centuries. ;’)
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