
Sun spots are areas on the surface where the temperature is slightly lower than its surroundings. They are caused by loops of magnetic field lines arcing up from the sun and back down again in a different spot. Because of this, sun spots come in pairs; one where the lines leave and one where they touch down again. The spots are cooler (around 4000c-5000c instead of 6000c-7000c) because the magnetism stops the usual processes that happen on the suns surface. Every 11 years, there are periods of extremely high sun spot activity, then it slows right down again, sometimes to almost nothing. No one yet knows why this 11 year cycle exists. Steve