We live at the whim of a “stormy star.” While our Sun sustains life on this planet, it is also prone to explosive acts of energy and violence. Once every 11 years, our Sun reaches a maximum level of activity and releases great outbursts of energy known as solar flares and coronal mass ejections (CMEs). These discharges are the equivalent of billions of megatons worth of TNT, with the energetic fast gamma- and X-ray energies hitting Earth in minutes and the heavier particles impacting our magnetic field days later. Luckily, not all of these outbursts are directed toward Earth, and we have a fleet of observatories in space and on the ground monitoring our Sun for these potential hazards. Most solar storms go unnoticed, but some wreak havoc with communications, satellites and pose a radiation hazard to astronauts in space. And as our society becomes ever more dependent on technology, the chances increase that a large solar storm could seriously impact civilization. Following are some of the biggest solar storms witnessed over the last two centuries.