Red dwarfs can be divided into two main groups: flare stars and more stabile, " friendly " stars. One good example of a flare star is UV Ceti, while one more friendly star is Barnard's Star. Around a flare star like UV Ceti (see image to right), flares can reach huge dimensions, increasing stellar energy output by many times in only a few seconds. Solar spots can form anytime and decrease luminosity by a few times. This will be a nightmare for settlers trying to make a new Earth here. On the other hand, Barnard's Star is far more friendly, but not safe. It still blows flares, terrorizing its planets, but such events are far more rare.