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X1.8 solar flare on 2011-09-07
ClassX1.8NOAA report
Peak22:382011-09-07 UTC
Duration12 min
Peak flux1.8e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 228 / 491 |
| Rank in year | 6 / 1319 |
| Other M/X flares that day | 0 |
| M/X flares that month | 35 |
| Solar cycle | Cycle 24 |
| Active region | AR 11283 (20 flares) |
Compared with the strongest flares of 2011
X6.9
X2.2
X2.1
X1.9
X1.9
X1.8
X1.5
X1.4
M9.3
M9.3
M7.4
M7.1
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.
← X2.1 2011-09-06M6.7 2011-09-08 →
About this page
A X1.8 flare that began 2011-09-07 22:32 UTC; No. 6 of 1,319 C-class-or-larger flares in 2011.