A short but weak solar maximum?

Chronological Encyclopedia of Discoveries in Space cover

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On July 4th NOAA released its monthly update of the solar cycle, showing the Sun’s sunspot activity in June. It is annotated and posted below.

June 2016 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. 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.

Not surprisingly, the time periods with no sunspots in June, including a 12 day stretch that just ended today, is reflected by the graph’s precipitous drop in June.

What is significant to me is the speed with which this solar maximum seems to be ending. Normally, weak solar cycles are also long solar cycles. The Sun not only doesn’t get as active, but the ramp up and down is extended, as is the period of the solar minimum. This is what happened during the solar minimum from 2007 to 2010. It was longer than normal, which meant that the solar maximum occurred much later than predicted by the 2007 predictions of the solar science communities (shown in green).

This recent stretch of blank days however is now suggesting that the solar maximum is going to end much sooner than the later 2009 prediction (shown in red). Even more astonishing, the numbers in June aligned with the 2007 high prediction, which would make this one of the shortest solar maximums on record!

I don’t expect these low numbers to continue. I expect sunspot activity to recover and continue, with the minimum likely occurring after 2018. If it does come sooner, however, that will once again be evidence suggesting we are heading for a Grand Minimum, with no sunspots for decades.



  • Phill O

    Will not throw out my neutral density solar filter yet, but considering the Lunt or Coronado solar scopes to make solar observing interesting over the next bit.

    Have the folk at the Solar Dynamics Observatory ramped up their research programs for solar minimum?

  • Localfluff

    Ancient Egyptians put huge efforts into building pyramids to honor the Sun and the shadows it casts. Now that we know that the Sun is really even more important to our survival than the day/night cycle evidently shows, we should make a similarly large effort to figure out what it is and how it works and what else. Heliocentricity is actually real, this is not an imaginary philosophy. We are stuck with it. And it own us, not only by the radiation which powers all life, but by even bending our very spacetime inside of us to capture us. The Sun is the obvious first priority of astronomy. But people do not seem to care much about it any more. I think that is a dangerous neglect.

    (And do not care about that localfloff guy, he is a misspelled character. The local fluff is the interstellar area around the Sun and our closest stars which is a bit denser than the surrounding interstellar medium, but still not even as dense as the average galactic interstellar medium. The local bubble has recently emptied our place in the galactic spiral arm. Some supernovas must have done that millions of years before we got here. The fluff is just a puff of smoke and gas from neighboring young stars that blow their winds at us. The fluff is the stuff which we live in, for the time being.)

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