Solar flares on April 21, 2003
The most powerful solar flare in 24 hours
M2.8 (strong) flare - April 21 at 2:07 PM
Solar activity index
Value as of the end of the day on April 21, 2003
Solar X-ray emission over the past 2 days
Chart of solar X-ray emission (1-8 Å) from April 20, 2003 to April 21, 2003
Time zone — UTC+01 (London) — summer time
List of solar flares for April 21, 2003
The total number of solar flares of class C and higher — 4 flares
C class — 3 | M class — 1 | X class — 0
| Class | begin | max | end | region |
|---|---|---|---|---|
| C1.8 | 22:23 | 22:47 | 23:13 | 337 |
| C1.3 | 20:29 | 20:35 | 20:41 | 339 |
| C2.3 | 16:51 | 16:59 | 17:03 | 337 |
| M2.8 | 13:54 | 14:07 | 14:14 | 338 |