Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. Extending above the photosphere or visible surface of the Sun , the faint, tenuous solar corona can't be easily seen from Earth, but it is measured to be hundreds of times hotter than the photosphere itself. Astronomers have long sought the source of the corona's heat in magnetic fields which loft monstrous loops of solar plasma above the photosphere. The new results confound the conventional theory which relies on heating the loops uniformly.
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