M-CLASS SOLAR FLARE: Sunspot AR3405 didn't look like it was going to explode, but it did on Aug. 22nd (2305 UT). NASA's Solar Dynamics Observatory recorded the extreme ultraviolet flash from an M1.1-class solar flare:
The flare lasted more than an hour--long enough to lift a CME out of the sun's atmosphere. If so, the CME could be heading for Earth. Confirmation awaits fresh data from SOHO coronagraphs.
Spaceweather.com