Sunspots, July 29, 2011. These three large sunspot groups are part of solar cycle 24, and show the difference a couple of years observing can make. In 2009 when the Sun was at its minimum of activity it had visible sunspots less than 30 percent of the year. In 2011 as solar activity increases the Sun has had visible sunspots over 99 percent of the time.
The dark cores of the small spots in the middle group are each about the size of the Earth. This photograph was taken with white light, and a solar filtered telescope.
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