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A substantial coronal hole rotated into a position where it is facing Earth (Aug. 9-11, 2017). Coronal holes are areas of open magnetic field that spew out charged particles as solar wind that spreads into space. If that solar wind interacts with our own magnetosphere it can generate aurora. In this view of the sun in extreme ultraviolet light, the coronal hole appears as the dark stretch near the center of the sun. It was the most distinctive feature on the sun over the past week. Movies are available at https://photojournal.jpl.nasa.gov/catalog/PIA21874
