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Birthday · August 14, 2005

Heating Coronal Loops

August 14, 2005

You share your birthday with the light of distant galaxies that has been traveling for millions of years just to arrive here, now, alongside...

Heating Coronal Loops

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APOD published August 14, 2005. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.

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Heating Coronal Loops

Original APOD · August 14, 2005

Why is the corona of the Sun so hot? 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. Detailed observations of coronal loops from the orbiting TRACE satellite are pointing more closely to the unidentified energy source. Recorded in extreme ultraviolet light, this and other TRACE images indicate that significant heating occurs low in the corona, near the bases of the loops as they emerge from and return to the solar surface. This tantalizing TRACE image shows clusters of the majestic, hot coronal loops which span 30 or more times the diameter of planet Earth.

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