Solar flares on October 18, 2025
The most powerful solar flare in 24 hours
M1.5 (strong) flare - October 18 at 4:51 AM
Solar activity index
Value as of the end of the day on October 18, 2025
Solar X-ray emission over the past 2 days
Chart of solar X-ray emission (1-8 Å) from October 17, 2025 to October 18, 2025
Time zone — UTC-06 (Denver) — summer time
List of solar flares for October 18, 2025
The total number of solar flares of class C and higher — 10 flares
C class — 6 | M class — 4 | X class — 0
| Class | begin | max | end | region |
|---|---|---|---|---|
| C2.8 | 22:28 | 22:34 | 22:39 | 4246 |
| M1.0 | 19:46 | 19:56 | 20:04 | 4246 |
| C8.0 | 15:40 | 15:54 | 16:01 | 4246 |
| C3.1 | 15:18 | 15:26 | 15:33 | 4246 |
| C3.0 | 11:32 | 11:37 | 11:51 | 4246 |
| M1.5 | 04:37 | 04:51 | 04:59 | 4246 |
| C6.0 | 01:35 | 01:48 | 01:55 | 4246 |
| M1.3 | 00:49 | 00:58 | 01:04 | 4246 |
| M1.2 | 00:32 | 00:39 | 00:44 | 4246 |
| C9.9 | 23:43 | 00:05 | 00:19 | 4246 |