The sun looks immutable, a boring celestial lightbulb that’s always turned on. But this fusion-powered ball of plasma is in constant flux. Every 11 years or so, it swings between slumber and an active, unruly epoch marked by sunspots and solar eruptions, such as flares and plasma outbursts. The sun is now approaching its maximum level of activity in the current cycle, and it’s not exactly behaving...
