Interesting solar flare research
See: https://www.youtube.com/watch?v=5xPBonKpHIM The Existential Threat of Solar Storms with Dr Benjamin Pope
One interesting high point is that using dendrochrolology evidence of a solar activity 80 times more intense than the Carrington event occurred in 774 CE while the latter does not even show up in the rings. Interesting. Fortunately these events are not common. They could last months or years which would preclude the recovery of advanced technological civilizations.