In science fiction, ion storms are a frequent menace to the Starship Enterprise. They may also pose a real-life threat. Real solar storms are caused when an eruption in the sun’s atmosphere ejects a huge cloud of ionized gas, called plasma, out into space. The plasma cloud consists of positively charged nuclei and negatively charged electrons and carries a magnetic field. If it’s headed in the right direction, and reaches Earth, this magnetic field causes a disturbance of Earth’s own magnetic field called a geomagnetic storm.
The disturbance changes the flow of electric currents in Earth’s field, sending trapped electrons towards the planet’s poles. Usually, the biggest consequence is a harmless and beautiful display of glowing curtains of light in the polar sky, called an aurora. Though radiation from solar storms is a hazard to astronauts in space, Earth’s magnetic field and atmosphere shield people on the ground. But, solar storms vary in intensity, and for severe ones, the consequences for our electronic-based society could be much worse.
In 2022 a computer scientist from the University of California published a study warning that the most severe solar storms may endanger the infrastructure of the internet. Evidence comes from history. The most severe solar storm on record, called the Carrington Event, happened in 1859. In North America, Europe, and Australia, its electric currents caused massive outages of, and damage to, the main communications system of the day—the telegraph system.
The study estimates that induced electrical currents from a similar solar storm, in the modern world, could cause a worldwide internet outage lasting for several months.