The massive Sunspot, number AR 3514 has fired the strongest solar flare of solar cycle 25. Sunspot 3514 erupted on Dec. 14th (1702 UT), producing a strong X2.8-class solar flare. This is the strongest flare of Solar Cycle 25 (so far) and the most powerful eruption the sun has produced since the great storms of Sept. 2017. NASA's Solar Dynamics Observatory recorded the extreme ultraviolet flash:
It's too soon to know for sure, but this explosion probably launched a fast coronal mass ejection (CME) with an Earth-directed component. The US Air Force is reporting a Type II solar radio burst, which typically comes from the leading edge of a CME. Based on the drift rate of the radio burst, the emerging CME's velocity could exceed 2100 km/s (4.7 million mph).