Solar flares on October 21, 2003
The most powerful solar flare in 24 hours
M3.7 (strong) flare - October 21 at 7:51 PM
Solar activity index
Value as of the end of the day on October 21, 2003
Solar X-ray emission over the past 2 days
Chart of solar X-ray emission (1-8 Å) from October 20, 2003 to October 21, 2003
Time zone — UTC-08 (Anchorage) — summer time
List of solar flares for October 21, 2003
The total number of solar flares of class C and higher — 6 flares
C class — 3 | M class — 3 | X class — 0
| Class | begin | max | end | region |
|---|---|---|---|---|
| M3.7 | 19:28 | 19:51 | 21:21 | 486 |
| M2.4 | 11:22 | 15:30 | 19:05 | — |
| C3.3 | 11:17 | 11:20 | 11:24 | — |
| C2.5 | 09:57 | 10:00 | 10:03 | 484 |
| C3.4 | 04:42 | 04:45 | 04:52 | — |
| M1.0 | 00:21 | 00:27 | 00:31 | 484 |