Sunspots and active regions
The following active regions with sunspot groups were visible on the Sun on April 21, 2005. 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) | |
|---|---|---|---|---|---|---|---|---|
| № 755 | S12 | E33 | 01 | 0020 | Alpha | Apr 25, 2005 | May 2, 2005 | May 15, 2005 |
| № 754 | S08 | W33 | 04 | 0030 | Beta | Apr 20, 2005 | Apr 27, 2005 | May 10, 2005 |
| № 752 | N02 | W44 | 04 | 0080 | Beta | Apr 19, 2005 | Apr 26, 2005 | May 9, 2005 |
Solar cycle progression
The average monthly sunspot number (SSN) from January 1976 to April 2005. The gray background is the average SSN index.
