Solar flares on April 21, 2013
The most powerful solar flare in 24 hours
C4.5 (normal) flare - April 21 at 7:39 PM
Solar activity index
Value as of the end of the day on April 21, 2013
Solar X-ray emission over the past 2 days
Chart of solar X-ray emission (1-8 Å) from April 20, 2013 to April 21, 2013
Time zone — UTC+01 (London) — summer time
List of solar flares for April 21, 2013
The total number of solar flares of class C and higher — 13 flares
C class — 13 | M class — 0 | X class — 0
| Class | begin | max | end | region |
|---|---|---|---|---|
| C2.7 | 20:59 | 21:15 | 21:32 | 1723 |
| C4.5 | 19:35 | 19:39 | 19:42 | 1726 |
| C2.9 | 17:00 | 17:03 | 17:06 | 1726 |
| C2.2 | 15:16 | 15:20 | 15:23 | 1726 |
| C1.0 | 12:38 | 13:03 | 13:09 | 1726 |
| C1.0 | 11:52 | 11:55 | 11:57 | 1726 |
| C1.8 | 11:21 | 11:24 | 11:26 | 1726 |
| C2.5 | 10:20 | 10:23 | 10:27 | 1726 |
| C1.3 | 08:30 | 08:34 | 08:40 | 1726 |
| C2.7 | 06:57 | 07:00 | 07:02 | 1726 |
| C1.4 | 06:04 | 06:14 | 06:18 | 1726 |
| C1.0 | 03:56 | 04:00 | 04:02 | 1726 |
| C3.6 | 02:02 | 02:09 | 02:16 | 1726 |