MDI tracks developing active regions across the near- and far-side of the Sun
At the beginning of the animated sequence (1 March 2001) MDI's view of the near side of the Sun gives no hint of any unusual activity.
After about 14 days (one half solar rotation) clear evidence for strong activity on the far side of the Sun becomes apparent.
After one complete solar rotation (28 days), a large active region is visible on the near side of the Sun. This region, which is now known as AR 9393, hosts the largest sunspot group to occur in 10 years.
Another two weeks pass by and MDI's view of the far side of the Sun shows that AR 9393 is still bubbling away. The high level of activity is still apparent at the lsat frame of the sequence.
Last Update: 1 September 2019