Space weather · 2003-10-29

Halloween storms — sequence of X-class flares from AR-486 including the saturated X28+ on 2003-11-04 (estimated X35–X45, largest GOES record). Kp pegged at 9 for two consecutive days. ADEOS-II spacecraft lost, GOES-12 affected, several airlines rerouted from polar to mid-latitude routes for ~72h, Swedish power grid logged voltage anomalies.