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Solar flares in May 2017
C-class5
M-class0
X-class0
LargestC3.32017-05-28
Sunspot number17.0NOAA SWPC
Flares per day (C and above)
Same month a year earlier
| Month | C | M | X | Largest |
|---|---|---|---|---|
| May 2016 | 10 | 0 | 0 | C3.5 |
| May 2017 | 5 | 0 | 0 | C3.3 |
Top 15 flares
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 2017-05-28 | 19:22 | 19:28 | 15 | C3.3 | N14W68 | 12659 |
| 2017-05-31 | 23:06 | 23:15 | 17 | C2.0 | N04E86 | 12661 |
| 2017-05-31 | 18:41 | 18:48 | 16 | C1.3 | – | – |
| 2017-05-31 | 20:53 | 21:06 | 24 | C1.3 | – | – |
| 2017-05-28 | 23:05 | 23:13 | 21 | C1.0 | N14W70 | 12659 |
All times UTC. Until June 2017 classes are NOAA's reports of the time (GOES-15 and earlier included a 0.7 scaling factor); later classes come from calibrated GOES-16/18 data, so the same flare reads about 1.4× larger. Do not compare the two periods directly.
About this page
5 flares of class C or larger in May 2017; by M/X count it ranks 544 of 565 months.