Hi Richard;
I also found it interesting that the sun seem to have a second cycle of 22 years, in addition to the regular 11 year solar cycle. I didn't quite grasp what this whole 22-year cycle was about, other than the effects it had on the heliosphere.
The 22 year cycle is an extension of the 11-year cycle, or to be more accurate, the 11 year sunspot cycle is a part of, and a consequence of, the 22-year magnetic polarity cycle.
The sun has an overall magnetic field which is, in general, oriented in a north-south polarity much as the earth's is. At solar minimum the sun's magnetic field is as close as it gets to a 'dipole' configuration (with a single north and south pole). Even in this quiet phase it has more than one north and south magnetic pole. As the magnetic cycle progresses, the sun's magnetic field 'winds up', becoming more and more tangled and complicated. Sunspots, each with their own north and south pole, appear, and become more numerous until, at solar max, the sun's magnetic field looks more like a pincushion than anything else. Magnetic field lines are twisted and tangled, and great loops of solar material are caught up in them in prominences and filaments, both of which are more common during this phase. At solar max the activity reaches its peak, and then begins to quiet down, with the generic solar magnetic field having reversed phase.
One 22-year (approximate) cycle represents one full phase change from a north-south minimum, through solar maximum where the field changes to south-north, through solar minimum, then back to max where a second polarity reversal occurs to a north-south, then back to a north-south solar minimum (caveat, I'm not actually sure where in the cycle the solar scientists start measuring, but it would make sense to start it at either a minimum or a maximum).
So, the 11-year sunspot cycle was recognized first, but now we recognize that the sunspot cycle is actually a part of the 22-year magnetic cycle.
Richard (guest) 31 May 2010 16:09