Monster X-class flare is most powerful solar eruption since 2017, could trigger auroras and major geomagnetic storms

The X-class solar flare, which exploded from the sun on Dec. 14, is the most powerful flare of the current solar cycle.   (Image credit: NASA/SDO)

The most powerful solar flare for more than six years has just exploded from the sun, and Earth is in the firing line. The X-class outburst has already triggered widespread radio blackouts and launched a massive plasma plume that could hit us in the coming days. 

The "amazing event" is another clear sign that the sun's explosive peak, the solar maximum, is right around the corner, experts say.