Thursday, February 27, 2014

X4.9 Flare is Cycle 24's 3rd Largest

At 0049 UTC February 25, returning Active Region 1967 (since renumbered AR1990) produced a strong X4.9 x-ray flare with radio sweeps and coronal mass ejection.  A proton storm began soon after. 

Most CME was directed off into space, and it was slow arriving. This planet did experience a moderate bow shock last night, causing a G2 level geomagnetic storm.  Europe experienced some truly amazing auroral displays from this storm, which is now apparently subsiding. 

Polar absorption of radio signals has been quite high for several days now, though low band VHF skip has remained strong around 30-33 MHz at mid-day when illumination of the F2 region is at maximum.  Here in California, copyable signals have come from the Northeastern, Mid-Atlantic, Midwestern, and South Central United States.

Region 1990, formerly region 1967. and before that region 1944, has showed remarkable longevity.  This is its third trip across the Earth-facing solar disk, and it's still making significant flares despite showing signs of magnetic decay.