70
A Year of Sunspots
(apod.nasa.gov)
A community for sharing astronomy-related news, content, research, photographs, etc.
When sharing photographs and articles, please make an effort to include source URLs.
Its part of the 11 year solar cycle. The bands move from the poles to the equator in during the cycle.
Edit: If your really interested: https://www.youtube.com/watch?v=fpNBIqjt_-4
Well damn, that's really interesting.