No image for the selected date
Sunspots and active regions
The following active regions with sunspot groups were visible on the Sun on September 17, 1999. 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) | |
|---|---|---|---|---|---|---|---|---|
| № 8702 | N22 | E25 | 02 | 0000 | BETA | Sep 20, 1999 | Sep 27, 1999 | Oct 11, 1999 |
| № 8700 | N14 | E28 | 25 | 0140 | BETA | Sep 20, 1999 | Sep 27, 1999 | Oct 11, 1999 |
| № 8699 | N22 | W42 | 13 | 0220 | BETA | Sep 15, 1999 | Sep 22, 1999 | Oct 6, 1999 |
| № 8695 | N21 | W07 | 03 | 0030 | BETA | Sep 18, 1999 | Sep 25, 1999 | Oct 8, 1999 |
| № 8693 | N13 | W47 | 01 | 0030 | ALPHA | Sep 15, 1999 | Sep 21, 1999 | Oct 5, 1999 |
| № 8692 | S26 | W44 | 16 | 0170 | BETA | Sep 15, 1999 | Sep 22, 1999 | Oct 6, 1999 |
| № 8690 | N16 | W65 | 23 | 0440 | BETA | Sep 13, 1999 | Sep 20, 1999 | Oct 4, 1999 |
Solar cycle progression
The average monthly sunspot number (SSN) from January 1970 to September 1999. The gray background is the average SSN index.
