“If this solar minimum keeps going past thirteen years, we’ve only had one cycle before that lasted nearly fourteen years. That was about the time of our American revolution! Solar cycle 4 started in 1785, and went from then to almost 1800.”
- David Hathaway, Ph.D., Heliophysics
Team Leader, NASA Marshall Space Flight Center
May 2, 2009 Huntsville, Alabama - A sunspot is a region of intense magnetic activity on the Sun's surface that are cooler than the rest of the sun. That's why they appear as dark spots. Sunspots are at temperatures of roughly 4,000 to 4,500 Kelvin, which is 6,740 to 7,640 degrees Fahrenheit, and are surrounded by hotter solar material around 5,800 Kelvin, or 9,980 degrees Fahrenheit.
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