Sunspots are storms on the sun’s surface that are marked by intense magnetic activity and play host to solar flares and hot gassy ejections from the sun’s corona. Scientists believe that the number of spots on the sun cycles over time, reaching a peak—the so-called Solar Maximum—every 11 years or so. Some studies indicate that sunspot activity overall has doubled in the last century. The apparent result down here on Earth is that the sun glows brighter by about 0.1 percent now than it did 100 years ago.