Solar flares on December 17, 2025
The most powerful solar flare in 24 hours
C1.3 (normal) flare - December 17 at 11:40 AM
Solar activity index
Value as of the end of the day on December 17, 2025
Solar X-ray emission over the past 2 days
Chart of solar X-ray emission (1-8 Å) from December 16, 2025 to December 17, 2025
Time zone — UTC+03 (Cheboksary)
List of solar flares for December 17, 2025
The total number of solar flares of class C and higher — 2 flares
C class — 2 | M class — 0 | X class — 0
| Class | begin | max | end | region |
|---|---|---|---|---|
| C1.0 | 12:48 | 12:55 | 13:00 | 4307 |
| C1.3 | 11:27 | 11:40 | 12:01 | 4307 |