Mon Sep 16, 2013 at 06:11 PM PDT
Solar Activity has Flatlined
The sun has one tiny spot at the peak of the solar cycle, September 16, 2013
NASA and Spaceweather
have no good explanations yet for the collapse in solar activity at the
peak of the sunspot cycle. They are perplexed by the inactivity.
Solar Activity Has Flatlined
The sun is disquietingly quiet according to NOAA and Spaceweather.
The quiet spell is a bit strange because 2013 is supposed to be a year of solar maximum, with lots of flares and sunspots. Supporting this view are data from NASA-supported observatories which show that the sun's magnetic field is poised to flip--a long-held sign that Solar Max has arrived. Nevertheless, solar activity is low.Four years ago I wrote The Sun's magnetic field is fading, no one knows why. I reported that the fading of the sun's magnetic field was a possible portent of a coming collapse in solar activity. Sunspots are not produced when the magnetic field of the spots declines below a critical threshold. The image below shows a complex spot on the left and a tiny spicule on the right. The spicule is, in effect, a spot that failed to form because the magnetic field was too weak.
Solar Activity Has FlatlinedALL QUIET ALERT: With the Sun's disk almost completely devoid of sunspots, solar flare activity has come to a halt. Measurements by NOAA's GOES 15 satellite show that the sun's global x-ray emission, a key metric of solar activity, has flatlined:This cycle will be the weakest solar cycle in 100 years according to solar physicists. Solar scientists are debating whether solar activity is collapsing completely. Matthew Penn of the National Solar Observatory proposed that the sun may be soon entering a new Maunder minimum, a period of almost no solar activity.
Penn offered another, more catastrophic option: the sunspot cycle might die altogether. His team uses sunspot spectra to measure their magnetic fields, and his data show a clear trend: the magnetic field strength in sunspots is waning. Penn's research shows that sunspots' magnetic field strength is declining over time. Sunspots can only form if the magnetic field is greater than around 1,500 Gauss, so if the trend continues, we could be headed for a time where no spots appear on the Sun's surface.
“If this trend continues, there will be almost no spots in Cycle 25, and we might be going into another Maunder Minimum,” Penn states. The first Maunder Minimum occurred during the second half of the 17th century. Almost no spots were seen on the Sun during this time, which coincided with Europe’s Little Ice Age.
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