Solar Flare WatchHome › Flare history › 1991
X1.1 solar flare on 1991-07-17
ClassX1.1NOAA report
Peak06:321991-07-17 UTC
Duration35 min
Peak flux1.1e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 371 / 491 |
| Rank in year | 43 / 3297 |
| Other M/X flares that day | 1 |
| M/X flares that month | 35 |
| Solar cycle | Cycle 22 |
| Position on disk | S25E46 |
| Active region | AR 6729 (10 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 |
|---|---|---|---|---|---|---|
| 21:04 | 21:24 | 117 | M3.0 | S26E18 | 6728 |
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.
← M7.3 1991-07-11X1.0 1991-07-18 →
About this page
A X1.1 flare that began 1991-07-17 06:18 UTC; No. 43 of 3,297 C-class-or-larger flares in 1991.