Solar Cycle 24

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Astronuc

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The fingerprint of the new solar cycle
The new solar activity cycle still puzzles all solar physicists due to its very slow start. The sunpot index for November 2009 is still only 4.2, well below many predictions (SIDC predictions: SM=6, CM=13). Although, the number of spotless days decreased strongly compared to the last two years, with multiple but small sunspot groups.
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http://sidc.oma.be/news/119/welcome.html [Broken]

A Long Filament Erupts (December 14, 2009)
http://soho.nascom.nasa.gov/pickoftheweek/old/11dec2009/


Solar Cycle 24 is off to a slow start.

http://www.spaceweather.com/images2009/15dec09/midi512_blank.gif?PHPSESSID=e4cknd2c58dnbuja23ubqbih15

http://www.spaceweather.com/images2009/15dec09/1035_anim2.gif?PHPSESSID=e4cknd2c58dnbuja23ubqbih15
 
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Astronuc

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So far, 65% of the days in December have brought sunspots--a sharp increase in percentages compared to earlier months of 2009 when sunspots were surpassingly rare. All six of December's sunspot groups have been members of new Solar Cycle 24. These numbers could herald the sun's awakening from the deepest solar minimum in nearly a century and a livelier sun in 2010.
Ref: http://www.spaceweather.com/archive.php?view=1&day=27&month=12&year=2009


Large Sunspot Group (December 18, 2009)
http://soho.nascom.nasa.gov/pickoftheweek/old/18dec2009/

For the first time in over a very quiet solar year, the Sun as seen by SOHO is sporting 5 active regions (Dec. 22, 2009). The brightest regions in the extreme UV image are magnetic active regions. And the brighter an area appears, then we know that its magnetic energy is stronger. Two of these regions are associated with dark sunspots when viewed in visible wavelengths; the other areas have not developed into sunspots yet. This activity could signal that the long solar minimum is beginning to give way to greater activity levels, but we will just have to wait and see.
Awakening Sun (December 25, 2009)
http://soho.nascom.nasa.gov/pickoftheweek/old/25dec2009/
 

Astronuc

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May 27, 2010

Solar Scientists Agree That the Sun's Recent Behavior Is Odd, but the Explanation Remains Elusive
The most recent solar minimum was both long and pronounced. But why?

MIAMI—In very rough terms, the sun's activity ebbs and flows in an 11-year cycle, with flares, coronal mass ejections and other energetic phenomena peaking at what is called solar maximum and bottoming out at solar minimum. Sunspots, markers of magnetic activity on the sun's surface, provide a visual proxy to mark the cycle's evolution, appearing in droves at maximum and all but disappearing at minimum. But the behavior of our host star is not as predictable as all that—the most recent solar minimum was surprisingly deep and long, finally bottoming out around late 2008 or so.

Solar physicists here at the semiannual meeting of the American Astronomical Society this week offered a number of mechanisms to shed light on what has been happening on the sun of late, but conceded that the final answer—or more likely answers—remains opaque. . . . .
 
I've been watching this solar cycle almost daily on spaceweather.com and to me personally its seems pretty normal. Sure it was off to a delayed start but still within the bounds of long-cycle variations. I'm one of those with the opinion that you cant really predict the sun anyway. Our observation of it is way to short-lived for that. Anyhow, March and April was quite active in terms of sunspots if I recall correctly, plus many filaments that produced flares. The past few weeks have been a tad too quiet though...IMO.
 

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