Sunspots and active regions
The following active regions with sunspot groups were visible on the Sun on April 13, 2004. 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) | |
|---|---|---|---|---|---|---|---|---|
| № 591 | S15 | E03 | 12 | 0040 | Beta | Apr 14, 2004 | Apr 21, 2004 | May 5, 2004 |
| № 588 | S15 | W66 | 05 | 0100 | Beta | Apr 9, 2004 | Apr 16, 2004 | Apr 29, 2004 |
Solar cycle progression
The average monthly sunspot number (SSN) from January 1975 to April 2004. The gray background is the average SSN index.
