http://www.swpc.noaa.gov/SWN/
http://www.space.com/11506-space-weather-sunspots-solar-flares-coronal-mass-ejections.html
http://hesperia.gsfc.nasa.gov/sftheory/flare.htm
http://solarscience.msfc.nasa.gov/CMEs.shtml
http://earthobservatory.nasa.gov/Features/SolarMax/
http://spaceweather.com/glossary/sunspotnumber.html
http://www.space.com/11506-space-weather-sunspots-solar-flares-coronal-mass-ejections.html
http://hesperia.gsfc.nasa.gov/sftheory/flare.htm
http://solarscience.msfc.nasa.gov/CMEs.shtml
http://earthobservatory.nasa.gov/Features/SolarMax/
http://spaceweather.com/glossary/sunspotnumber.html