Solar flares on September 21, 2011
The most powerful solar flare in 24 hours
M1.8 (strong) flare - September 21 at 3:23 PM
Solar activity index
Value as of the end of the day on September 21, 2011
Solar X-ray emission over the past 2 days
Chart of solar X-ray emission (1-8 Å) from September 20, 2011 to September 21, 2011
Time zone — UTC+03 (Riga)
List of solar flares for September 21, 2011
The total number of solar flares of class C and higher — 11 flares
C class — 10 | M class — 1 | X class — 0
| Class | begin | max | end | region |
|---|---|---|---|---|
| C2.0 | 23:31 | 23:36 | 23:40 | 1295 |
| C2.1 | 19:47 | 19:49 | 19:51 | — |
| C2.3 | 19:13 | 19:16 | 19:20 | — |
| C2.8 | 18:21 | 18:26 | 18:30 | 1295 |
| C2.7 | 17:37 | 17:38 | 17:41 | 1295 |
| C2.6 | 17:21 | 17:23 | 17:26 | 1295 |
| M1.8 | 15:04 | 15:23 | 15:45 | 1302 |
| C3.9 | 14:17 | 14:24 | 14:28 | 1301 |
| C1.9 | 10:37 | 10:41 | 10:47 | 1295 |
| C2.7 | 03:55 | 04:07 | 04:14 | 1301 |
| C3.0 | 00:38 | 00:42 | 00:46 | 1295 |