At http://news.sciencemag.org/sciencenow/2010/09/say-goodbye-to-sunspots.html … it is recognised that sun spot activity has declined – at the moment, in early January. The surface of the Sun is clear – or nearly so. Sun spots are thought to be upwellings of the Sun's magnetic field which traps ionised plasma – or electrically charged superheated gas, at the surface. The Sun also has an 11 year cycle during which it peaks (lots of sun spots) and declines (known as the solar minimum). The problem is that the current solar minimum should have ended a couple of years ago – but the current one has persisted and is at the moment the longest cycle during the last 100 years. According to a paper published by the International Astronomical Union Symposium (No 273) it is the magnetic strength of sun spots that have waned, from 2700 gauss to around 2000 gauss. If it should drop below 1500 gauss in the next few years it will be unable to produce any sun spots at all.
As surprising as this may seem sun spots have been known to disappear in the past – during the Maunder Minimum for example, between 1645 and 1715AD, a particularly cold phase of the Little Ice Age. However, we may note that sun spots did occurr during other phases of the Little Ice Age so other factors are involved as well.
The comments raise the idea of a change in the barycentre of the universe, popular in some circles at the moment, and another one says the Sun's nucleur reactor, which he says is at its core, has a half cycle of nucleur fusion followed by fission over the other half cycle. Sun spots peak when these reactions are midway through their half cycles (see www.sittampalam.net).