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Solar flares from active region 6818
C5
M6
X2
LargestX3.31991-09-07
Span4 days
Flares by day
3
6
3
1
All flares
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 1991-09-06 | 05:36 | 06:54 | 102 | C5.2 | S13W29 | 6818 |
| 1991-09-06 | 16:05 | 16:06 | 8 | C6.0 | S11W38 | 6818 |
| 1991-09-06 | 19:09 | 19:10 | 9 | C3.0 | S10W39 | 6818 |
| 1991-09-07 | 06:29 | 07:57 | 133 | M2.1 | S13W45 | 6818 |
| 1991-09-07 | 09:40 | 10:16 | 102 | M4.1 | S11W48 | 6818 |
| 1991-09-07 | 12:33 | 12:48 | 74 | M2.1 | S11W46 | 6818 |
| 1991-09-07 | 18:21 | 18:51 | 38 | M1.9 | S11W51 | 6818 |
| 1991-09-07 | 19:11 | 19:35 | 70 | X3.3 | S11W50 | 6818 |
| 1991-09-07 | 23:49 | 23:53 | 20 | C7.1 | S11W54 | 6818 |
| 1991-09-08 | 01:43 | 01:50 | 44 | M2.1 | S11W54 | 6818 |
| 1991-09-08 | 09:06 | 09:16 | 43 | X1.0 | S13W58 | 6818 |
| 1991-09-08 | 18:29 | 18:31 | 36 | C7.5 | S11W64 | 6818 |
| 1991-09-09 | 05:55 | 06:08 | 58 | M2.0 | S14W72 | 6818 |
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 6818 produced 13 C+ flares between 1991-09-06 and 1991-09-09.