Sunspots and active regions
The following active regions with sunspot groups were visible on the Sun on April 21, 2006. 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) | |
|---|---|---|---|---|---|---|---|---|
| № 874 | S01 | W09 | 09 | 0060 | Beta | Apr 21, 2006 | Apr 28, 2006 | May 11, 2006 |
| № 871 | S06 | W77 | 01 | 0010 | Alpha | Apr 16, 2006 | Apr 23, 2006 | May 6, 2006 |
Solar cycle progression
The average monthly sunspot number (SSN) from January 1977 to April 2006. The gray background is the average SSN index.
