Taken halfway between first and second contact, this image appears purple because of the filter on the telescope. Notice the small dark spot near the bottom left of the sun’s disk (at about the 7 o’clock position). This is a sunspot, a place on the sun that is slightly cooler than the surrounding surface because of increased magnetic activity. The sun has an eleven-year cycle of sunspot activity. In 2006, the sun was near its most quiet phase, called solar minimum.

Photo by Eric Blackhurst, OPT

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