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X1.5 solar flare on 1981-05-13
ClassX1.5NOAA report
Peak04:281981-05-13 UTC
Duration150 min
Peak flux1.5e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 258 / 491 |
| Rank in year | 21 / 4022 |
| Other M/X flares that day | 1 |
| M/X flares that month | 20 |
| Solar cycle | Cycle 21 |
| Position on disk | N11E58 |
| Active region | AR 3106 (28 flares) |
Compared with the strongest flares of 1981
X5.9
X5.5
X4.0
X3.6
X3.5
X3.1
X3.0
X2.7
X2.6
X2.5
X2.4
X2.3
Other M/X flares that day
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 17:52 | 18:07 | 88 | M1.1 | N13E60 | 3112 |
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.
← X1.0 1981-05-05X1.1 1981-05-16 →
About this page
A X1.5 flare that began 1981-05-13 03:40 UTC; No. 21 of 4,022 C-class-or-larger flares in 1981.