Every now and then, you’ll hear a story on the news about a new solar storm.

They happen all the time, but they’re usually not intense enough to affect Earth beyond some neat light shows around the poles. But sometimes, they can be really powerful, and they have the potential to wreak all kinds of havoc.

In 1859, Earth experienced the biggest solar storm ever recorded. Back then, it didn’t cause much damage, but if we ever get hit by another storm like it… we’re kinda toast. Solar storms are just outbursts or explosions caused by magnetic activity on the Sun.

Sometimes, as part of one, the Sun will release coronal mass ejections, or CMEs, which are giant waves of magnetism and the hot, electrically-charged gas called plasma. If a CME hits Earth, it interacts with our magnetic field and causes disturbances called geomagnetic storms. These storms can create beautiful things like the Northern and Southern Lights, but they can also cause all kinds of trouble.

The solar storm in 1859 was big enough to send two CMEs right at us. We don’t know exactly how strong it was because we didn’t have satellites to measure it, but research suggests it was the most powerful storm in the last 500 years. When the first CME reached Earth, the Northern Lights were seen as far south as Colombia, and the Southern Lights were seen as far north as Queensland.

In some places, it was even bright enough to read in the middle of the night. But the new-fangled telegraph industry also experienced all kinds of electrical failures. Machines sent and received false signals, and even threw sparks that, in some cases, started fires.

Other technology, mostly scientific instruments, went similarly haywire. At the time, no one knew what was happening, but this became some of the first evidence that auroras are caused by electromagnetism. Right after these events, two amateur astronomers named Richard Carrington and Richard Hodgson independently saw a big, white flare on the surface of the Sun, which turned out to be the second CME!

But except for a few broken telegraph machines, everyone survived the solar storm, and it’s now called the Carrington Event. It could have been called the Richards Event, but sometimes life lets you down. Now, these days, we rely on technology way more than we did in 1859.

And if a solar storm of the same magnitude as the Carrington Event hit us… it’d be rough. We’ve put a lot of stuff into space, and we rely on it really heavily. GPS, cell phones, wireless credit card transactions (like when you pay at the pump for gas), they’re all satellite-based technologies.

And solar storms are especially dangerous to satellites. Energetic particles from CMEs can damage their solar panels, mostly by short-circuiting them. And static charges can build up on the satellites’ bodies, which can cause more short-circuiting or false signals.

And even worse, a powerful geomagnetic storm could even cause satellites to fall out of orbit. The upper atmosphere is filled with charged particles, which can be affected by geomagnetic storms. A bunch of things can happen, but they basically add up to a ton of built-up energy, which means a lot of heat.

And hot gases expand. Satellites just outside the atmosphere would suddenly be enveloped in a hot, cushy cloud, which would create drag that would slow them down. And if they got slow enough, they’d fall to Earth.

Fortunately, satellite engineers are aware of all of this. And while they’re not able to fully compensate for the damage from an angry Sun, they are working on developing more resilient satellites. But the impacts of an enormous storm wouldn’t be limited to miles above the ground!

We’d be in trouble down here, too. Besides the fact that our cell phones would stop working, we’d also be sitting in the dark. See, those giant boxes you see along power lines are transformers, and they convert electricity running through power lines into something your house can use.

Unfortunately, geomagnetic storms can cause induced currents in them, which can overload them and make them explode. This is actually the same idea behind what made telegraph machinery spark in the 1800s. It’s estimated that if we had a Carrington Event today, most of the United States would go dark.

And it would take years to replace the transformers and repair that kind of damage. Our power grids just aren’t prepared for a giant solar storm, but at least we’re getting better at predicting the Sun’s activity, thanks to organizations like NASA and NOAA. Now, if we knew an especially nasty solar storm was on the way, we could at least shut down transformers so they don’t short-circuit.

Then, we’d have only a week or so of Mad-Max-style pandemonium instead of years. So, we’d be in trouble if the Sun decides to throw a temper tantrum, but it could always be worse! Other stars like the Sun can produce massive explosions, called superflares.

And they have energies between 10 and 1000 times that of a Carrington Event. And that would probably cause total chaos. But thankfully, recent papers suggest that the Sun probably isn’t capable of producing a superflare, because its upper atmosphere isn’t energetic enough.

So if we ever experience a colossal solar storm… just remember: it could have been way worse! Thanks for watching this episode of SciShow Space! If you’d like to learn even more about solar flares and solar storms, you can watch one of the latest space news episodes, where we talked about the strongest solar flare in over a decade.