Big #sunspot AR3363 just produced a significant #solar #flare, a long-duration M6-class event during the early hours of July 18th. NASA's Solar Dynamics Observatory recorded the blast near the sun's southwestern limb:
Energetic protons accelerated by the flare have reached Earth and are now peppering the top of our planet's atmosphere. This is called a "radiation storm." According to data from NOAA's GOES-16 satellite, it is a category S2 event.
Although the explosion was not X-class, it was more powerful than many X-flares would be. Why? Because it lasted so long. The flare's X-ray output was above M5 for more than an hour and above M1 for nearly 4 hours. It had plenty of time to lift a substantial CME out of the sun's atmosphere.
