Sunspot
Sunspots are cooler than the rest of the Sun.  But many scientists think that when there are many sunspots, the Sun actually gets hotter.  This affects the weather here on Earth, and also radio reception.  If this is true, then without sunspots, the Earth might become cooler.  In the same way, if there were more sunspots, the Earth might become hotter, and there could be less rain.  This would make more droughts on the Earth.  Droughts are a long time with no rain.  Without rain, crops that people eat would not grow.  Scientists study sunspots and other solar phenomena, so they can know what they do to Earth.  The temperature of a sunspot is 4780°K.  This is cold when compared to other areas on the surface of sun.