Below is the June graph of sunspot activity released by NOAA yesterday. As I do every month, I am posting it here, annotated to give it some context.
After three months of slightly increased sunspot activity, the Sun in June was essentially blank, with sunspots visible on its facing hemisphere on only five days. In addition, the 36 day stretch of spotless days that began in May and stretched through most of June was the longest such stretch since the last minimum in 2009.
The graph above has been modified to show the predictions of the solar science community for the previous solar maximum. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction, extended in November 2018 four years into the future.
Even while the solar minimum continues and heads for its low point, the first indications of the next solar solar cycle have appeared:
[A] sunspot from the next solar cycle has emerged in the sun’s southern hemisphere. Numbered “AR2744”, it is inset in this magnetic map of the sun’s surface from NASA’s Solar Dynamics Observatory:
How do we know this sunspot belongs to Solar Cycle 25? Its magnetic polarity tells us so. Southern sunspots from old Solar Cycle 24 have a -/+ polarity. This sunspot is the opposite: +/-. According to Hale’s Law, sunspots switch polarities from one solar cycle to the next. AR2744 is therefore a member of Solar Cycle 25.
The article at the link refers to another second next-cycle sunspot earlier in the month, but this is incorrect, as that active region never turned into a sunspot. Still, as noted at the link, this isn’t the first sunspot or active region belonging to the next solar cycle to appear, and its appearance is very significant. It suggests that we will have an upcoming solar maximum, and are not heading into a grand minimum, when no sunspots are visible for decades.
Their appearance however does not mean that solar minimum is over. On the contrary, the solar cycles typically overlap by one or two years, with new sunspots for the next solar cycle appearing even as the Sun ramps down to minimum and remains relatively inactive for many months.
I cannot deny that I will be disappointed if a grand minimum does not occur. Such an event would have been a wonderful opportunity for solar scientists to get answers to their many questions about the Sun’s solar cycles that today remain unanswered and will likely not be answerable while the Sun follows its behavior of the last three hundred years.
At the same time, if the upcoming solar cycle is weak, as has been predicted by some solar scientists, it will help confirm some theories that try to explain the Sun’s behavior.
We can only wait and observe to find out.
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