Sunspots and active regions
The following active regions with sunspot groups were visible on the Sun on April 21, 2008. Coordinates are given as of the end of the day.
| Group ID | Location | Number of sunspots | Area (msh) | Type | CM Passage | Disappearance (W90) | Reappearance (W270) | |
|---|---|---|---|---|---|---|---|---|
| № 991 | S10 | E17 | 02 | 0020 | Alpha | Apr 23, 2008 | Apr 30, 2008 | May 14, 2008 |
Solar cycle progression
The average monthly sunspot number (SSN) from January 1979 to April 2008. The gray background is the average SSN index.
