...A group of experts convened by NASA and the National Oceanic and Atmospheric Administration (NOA) fomed a Solar Cycle 24 Prediction Panel. The panelists generally split into two camps. Some forcasted a strong solar maximum, with a lot of sunspots that ramped up quickly, reaching a peak sometime in late 2011. Others predicted a weak maximum, with fewer sunspots whose numbers would peak around mid-2012.
...To everyone's suprise, however, the Sun has decided to fall behind schedule. The scientists in both camps expected the Sun to reach its sunspot minimum in March 2008, after which the Sun would begin ramping up to the new solar maximum. Instesad, the Sun decided to remain quieter than it has been in almost a century. It is now more than a year since March 2008, and the Sun remains nearly blank, in one of the deepest solar minima on record.
... The Ulysses spacecraft spent the last two decades in polar orbit around the Sun. Ulysses found that during that period the solar wind's speed dropped by about 3%, its temperature dropped by 13%, and its density dropped by 20%. Such changes mean that the solar wind is exerting less pressure on the intergalactic medium, thereby shrinking the heliosphere and allowing more cosmic rays from our galaxy to leak into the solar system.