Sunspots and active regions
The following active regions with sunspot groups were visible on the Sun on April 16, 2001. 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) | |
|---|---|---|---|---|---|---|---|---|
| № 9429 | N08 | E46 | 01 | 0120 | Alpha | Apr 21, 2001 | Apr 28, 2001 | May 11, 2001 |
| № 9427 | S08 | W68 | 01 | 0020 | Alpha | Apr 12, 2001 | Apr 19, 2001 | May 3, 2001 |
| № 9426 | S09 | W20 | 02 | 0010 | Alpha | Apr 16, 2001 | Apr 23, 2001 | May 6, 2001 |
| № 9424 | S17 | W66 | 03 | 0020 | Beta | Apr 12, 2001 | Apr 19, 2001 | May 3, 2001 |
| № 9422 | S12 | W34 | 04 | 0020 | Beta | Apr 15, 2001 | Apr 22, 2001 | May 5, 2001 |
| № 9420 | S07 | W63 | 01 | 0020 | Alpha | Apr 13, 2001 | Apr 19, 2001 | May 3, 2001 |
| № 9418 | N26 | W76 | 04 | 0170 | Beta | Apr 11, 2001 | Apr 18, 2001 | May 2, 2001 |
| № 9415 | S21 | W91 | 04 | 0350 | Beta | Apr 10, 2001 | Apr 17, 2001 | May 1, 2001 |
Solar cycle progression
The average monthly sunspot number (SSN) from January 1972 to April 2001. The gray background is the average SSN index.
