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X1.0 solar flare on 1991-09-08
ClassX1.0NOAA report
Peak09:161991-09-08 UTC
Duration43 min
Peak flux1.0e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 419 / 491 |
| Rank in year | 54 / 3297 |
| Other M/X flares that day | 4 |
| M/X flares that month | 26 |
| Solar cycle | Cycle 22 |
| Position on disk | S13W58 |
| Active region | AR 6818 (13 flares) |
Compared with the strongest flares of 1991
X12.0
X12.0
X12.0
X12.0
X12.0
X10.0
X10.0
X9.4
X7.1
X6.1
X5.5
X5.3
Other M/X flares that day
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 01:43 | 01:50 | 44 | M2.1 | S11W54 | 6818 | |
| 08:13 | 08:18 | 13 | M1.0 | – | – | |
| 11:28 | 11:32 | 27 | M2.7 | S12E09 | 6820 | |
| 20:35 | 20:44 | 35 | M1.6 | – | – |
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.
← X3.3 1991-09-07M6.1 1991-09-24 →
About this page
A X1.0 flare that began 1991-09-08 09:06 UTC; No. 54 of 3,297 C-class-or-larger flares in 1991.