Long-lasting solar flare

In the morning hours of 5 October 2012, the Sun produced a relatively weak B7.8 flare. Interesting were its atypical x-ray evolution and its very long duration. Indeed, after starting at 03:17UT, it reached its maximum x-ray intensity only at 07:30UT. Once it ended at 10:46UT, the flare had lasted for an incredible 7 hours and 29 minutes – one of the longest so far the current solar cycle (which began in 2008). The ejected plasma cloud sparked a moderate geomagnetic storm on Earth on 8 October.