Solar flares on April 21, 2011
The most powerful solar flare in 24 hours
C8.5 (normal) flare - April 21 at 10:48 AM
Solar activity index
Value as of the end of the day on April 21, 2011
Solar X-ray emission over the past 2 days
Chart of solar X-ray emission (1-8 Å) from April 20, 2011 to April 21, 2011
Time zone — UTC+01 (London) — summer time
List of solar flares for April 21, 2011
The total number of solar flares of class C and higher — 4 flares
C class — 4 | M class — 0 | X class — 0
| Class | begin | max | end | region |
|---|---|---|---|---|
| C4.5 | 22:51 | 23:07 | 23:39 | 1195 |
| C4.9 | 15:37 | 15:51 | 16:00 | 1195 |
| C8.5 | 10:38 | 10:48 | 10:58 | 1195 |
| C1.0 | 09:31 | 09:38 | 09:50 | 1195 |