Wildfires raged across California during the week of 22nd October 2003. The thick smoke produced by the huge forest fires dimmed the sun to such an extent that you could look at it directly (never a good idea). On glancing at the sun people were started to big blotches on its disc.
Sunspots on the sun in October 2003
These black blotches were sunspots, "a spot or patch that appears from time to time on the sun's surface, appearing dark by contrast with its surroundings".
It's very rare, and very dangerous to the eyes, to be able to see these sunspots.
They are often the site of increased solar flare activity and can be responsible for disrupting communication on Earth, but also produce dazzling displays of aurora.