Captured on March 29, 2011 by NASA's Solar Dynamics Observatory (SDO), this photograph of the sun was taken during an eclipse. "Twice a year, SDO enters an eclipse season where the spacecraft slips behind Earth for up to 72 minutes a day," NASA explained. "Unlike the crisp shadow one sees on the sun during a lunar eclipse, Earth's shadow has a variegated edge due to its atmosphere, which blocks the sun light to different degrees depending on its density. Also, light from brighter spots on the sun may make it through, which is why some solar features extend low into Earth's shadow."

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Image: NASA.

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