Solar Flare WatchHome › Flare history › Region ranking
Solar flares from active region 6504
C12
M3
X0
LargestM2.81991-02-25
Span12 days
Flares by day
1
3
2
1
2
3
1
2
All flares
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 1991-02-16 | 09:55 | 10:02 | 14 | C6.4 | S16E68 | 6504 |
| 1991-02-18 | 06:33 | 07:30 | 66 | M2.6 | S18E48 | 6504 |
| 1991-02-18 | 16:35 | 16:49 | 29 | C8.1 | S18E43 | 6504 |
| 1991-02-18 | 22:01 | 22:08 | 45 | M1.0 | S17E42 | 6504 |
| 1991-02-19 | 01:01 | 01:16 | 53 | C7.1 | S15E41 | 6504 |
| 1991-02-19 | 04:36 | 04:43 | 29 | C4.1 | S13E32 | 6504 |
| 1991-02-21 | 15:54 | 15:55 | 5 | C3.0 | S13W01 | 6504 |
| 1991-02-24 | 16:03 | 16:10 | 26 | C6.8 | S17W33 | 6504 |
| 1991-02-24 | 21:07 | 21:33 | 38 | C9.8 | S17W36 | 6504 |
| 1991-02-25 | 12:03 | 12:09 | 19 | C4.5 | S18W44 | 6504 |
| 1991-02-25 | 14:09 | 14:11 | 22 | C2.7 | S17W46 | 6504 |
| 1991-02-25 | 16:01 | 16:01 | 8 | M2.8 | S17W45 | 6504 |
| 1991-02-26 | 12:20 | 12:26 | 23 | C5.2 | S17W55 | 6504 |
| 1991-02-27 | 01:20 | 01:21 | 11 | C5.7 | S16W63 | 6504 |
| 1991-02-27 | 05:28 | 05:29 | 23 | C3.1 | S17W65 | 6504 |
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
NOAA active region 6504 produced 15 C+ flares between 1991-02-16 and 1991-02-27.