Solar flares on September 17, 2025
The most powerful solar flare in 24 hours
C2.8 (normal) flare - September 17 at 8:04 PM
Solar activity index
Value as of the end of the day on September 17, 2025
Solar X-ray emission over the past 2 days
Chart of solar X-ray emission (1-8 Å) from September 16, 2025 to September 17, 2025
Time zone — UTC-04 (Dover) — summer time
List of solar flares for September 17, 2025
The total number of solar flares of class C and higher — 6 flares
C class — 6 | M class — 0 | X class — 0
| Class | begin | max | end | region |
|---|---|---|---|---|
| C1.7 | 21:34 | 21:38 | 21:40 | 4220 |
| C2.8 | 19:55 | 20:04 | 20:13 | 4217 |
| C1.6 | 18:42 | 18:47 | 18:51 | 4220 |
| C1.4 | 18:32 | 18:38 | 18:42 | 4220 |
| C2.3 | 11:35 | 11:41 | 11:43 | 4216 |
| C1.7 | 08:13 | 08:19 | 08:21 | 4216 |