Wednesday, September 06, 2017

Biggest solar flare in years causes short wave fadeouts

At 1200 UTC on 6 Sept 2017, an X9.3 solar flare took place in active region 2673. This is the biggest solar flare of Cycle 24, not to mention the biggest in at least ten years.  In the last few days, this region has also produced a smaller X class flare, and several of M class.  It has also been active enough to run the daily solar flux up to 140 yesterday, though it has declined to "only" 133 today.  15 meters has good propagation in the Western Hemisphere.

Today's major radio fadeout effects took place in Europe, which was on the sunlit side of the planet at the time.  The fadeout was severe, and long lasting.  It affected frequencies all the way up to low band VHF.

A number of highly geoeffective coronal mass ejections (CMEs) are in transit to this planet, and a significant magnetic storm is likely at any time.  This could cause some pretty impressive aurora, though the moon is rather bright at present.  Auroral propagation chasers should be ready.

This activity is more evidence that solar flares are not limited to the peaks of cycles.  The active region, which is huge, comes pretty close to the bottom (and end) of Cycle 24.