From Tom DF5JL on the UDXF newsgroup:
The weekend was really good for surprises: Although solar wind speeds were
low, the storms we observed were due to the enhanced magnetic field with
sustained southward orientation associated with the passage of a magnetic
cloud, which in turn coalesced with the 20th August coronal
mass ejection
(CME). Negative Bz values were observed since about 1500 UT on August 25,
and finally reached a value of -17nT.
Not only did a coronary mass
ejection (CME) give us a magnetic strom of class G3 (k = 7), suddenly also a
big sunspot appeared. We remember: For most of the year 2018, the solar disk
was empty, without even the slightest sunspot. But this weekend suddenly
there was a rapidly expanding spot with two dark cores as wide as the
earth.
The new sunspot AR2720 is not only large, its magnetic polarity is
also reversed compared to the sunspots of the current solar cycle 24. So, could this be the first big sunspot of the coming solar cycle? A new solar cycle always starts with a sunspot, in which magnetic north and south poles are reversed compared to the previous spots.
However, the
relative equatorial proximity of this spot speaks against it - a sure sign
of the beginning of a new cycle would be in addition to the reverse polarity
of a relative equatorial distance. Further
observations are
necessary.
As well as better conditions on the shortwave ;)
73 Tom
DF5JL
