As a background, I used to work on the FAA - WAAS[0] a system that provides more accurate GPS and more importantly provides realtime integrity reports of GPS for users. A big part of my work was studying ionospheric storms and how they affected GPS. We made the majority of analysis from collected data from the late 90s and onward, the sad truth is that we have no real idea of what a massive solar event would do to satellites and the earth.

Satellites in general have a very hard time discharging large amounts of current, because there simply is no ground and the possibility of a Carrington Event[1] in the modern age is simply frightening. An event of this size today could possibly knock out thousands of satellites at once -- including the entire GPS constellation.

The effects on earth could be very damaging too, what would happen we aren't quite certain. However, you could see arcs from power lines or any long distance wire as it would provide easy paths for electrons. This also could affect any computers much like an EMP blast. We could be looking at a large percentage of all electronics broken. So we might suddenly have large areas, with no power, no electronics, and no communication.

After spending lots of time learning about the science behind these storms, to me this is the stuff of nightmare fuel.

[0]: https://en.wikipedia.org/wiki/Wide_Area_Augmentation_System

[1]: https://en.wikipedia.org/wiki/Solar_storm_of_1859