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This
coronagraph image was taken by NASA's Solar and Heliospheric
Observatory (SOHO) spacecraft. A coronagraph is a special type
of telescope that works by creating an artificial eclipse. Ordinarily,
the bright light of the sun drowns out most of the detail of
the corona, but a coronagraph uses a circular shade to block
out the sun so the surrounding corona can be seen. In this image,
you can see two coronal mass ejections-one
at two o'clock, the other at eight o'clock-erupting from opposite
sides of the sun. |
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Compare
the coronagraph with this petroglyph, near Una Vida at Chaco Canyon.
The petroglyph is thought by some to represent the total solar
eclipse of AD 1097. The curly projections could have been the
illuminated corona, which glows brightly during totality. The
curly halo might also suggest the sun was undergoing a coronal
mass ejection, with coronal material being flung outward toward
the earth. |
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