To understand the solar cycle, notice how the sun sleeps

The sun is such a constant in our lives that it can be difficult to imagine our star ever changing. But the sun can be quite variable. There are times when its magnetic field is turbulent and generates many sunspots and other times when it is quiet and dormant. Since the 1800s, we've known that these active and passive periods follow an 11-year pattern known as the solar cycle. But even after centuries of observation, we still have a difficult time predicting exactly when solar maximum will occur and just how intense it will be. This is important because solar activity can have a significant impact on our modern technological infrastructure.