An M9.6 solar flare (R2-moderate) peaked today at 16:43 UTC.

An M9.6 solar flare (R2-moderate) peaked today at 16:43 UTC. That was close! An M9.6 solar flare (R2-moderate) peaked today at 16:43 UTC. That is indeed just short of being an X-class solar flare. What sunspot region produced this mighty eruption? Indeed none of the sunspot groups on the earth-facing disk are likely to produce such an event so we quickly focus our eyes on the solar limb. It is there in the south-east we see this eruption signaling the imminent arrival of perhaps a complex sunspot region? Let’s find out in a couple of days... If this eruption produces a coronal mass ejection it is of course very likely to not be aimed at Earth. .... Earth-orbiting satellites have just detected an solar flare from a sunspot group hiding behind the sun’s southeastern limb. In fact, the explosion was probably X-class albeit partially eclipsed by the edge of the sun. NASA’s Solar Dynamics Observatory recorded the extreme ultraviolet flash. Although the underlying sunspot group is hidden from view, it nevertheless managed to touch Earth. Radiation ionized the top of our planet’s atmosphere, causing a shortwave radio blackout over North America. Ham radio operators and aviators may have noticed loss of signal and other unusual propagation effects for up to an hour after the peak of the flare (1643 UT). The source of this explosion may be the same farside sunspot we discussed on May 12th. If so, the sun’s rotation should turn it to face Earth later this week.