The lights you see are caused by large explosions on the sun's surface ejecting material into space--called solar flares which hit the Earth within 30 minutes causing all kinds of communications and electrical grid issues (search the Carrington event of 1859) and then a few days later the coronal mass ejection material hits us which is what causes the lights. If you're in an airplane when a major solar flare hits you receive the equivalent of an entire years worth of solar radiation in that instance (ie cancer, damage to your DNA) At scale these explosions could swallow the Earth, sometimes a few times over depending upon size.

They are rated on a scale with X class being the largest. The sun released several X class flares over the past week, which isn't exactly common and solar activity is actually the primary driver of weather on Earth--the reason Milton intensified so quickly if because the sun experienced an X class flare almost every day this past week. The only protection we have on earth from these events is our magnetic field, which is significantly weakening due to pole shift (the N and S poles are moving) and galactic current sheet activity (the effects of this can be seen throughout the planets of our solar system already). With the magnetic shield weakening these sun events are causing more damage on Earth with smaller sizes events.

An X20 or so solar flare could be strong enough to cause a killshot--complete power grid failure for the 25% of the Earth directly facing the sun upon it's release. We've experienced about 3 solar flares this year in the x7-10 range, including back to back 7 and 9s last weekend. Yesterday's CME storm was the highest I've seen since paying attention at KP8, and that was an X1+ flare. When they got back to back is particularly bad because Earth is mostly unprotected from the second wave.

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