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X1.0 solar flare on 1981-04-18
ClassX1.0NOAA report
Peak10:541981-04-18 UTC
Duration40 min
Peak flux1.0e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 394 / 491 |
| Rank in year | 32 / 4022 |
| Other M/X flares that day | 5 |
| M/X flares that month | 87 |
| Solar cycle | Cycle 21 |
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 |
|---|---|---|---|---|---|---|
| 01:20 | 01:35 | 53 | M5.5 | N10W37 | 3038 | |
| 05:49 | 06:07 | 121 | M3.5 | N10W38 | 3038 | |
| 07:14 | 07:20 | 27 | M1.9 | N10W38 | 3038 | |
| 08:11 | 08:11 | 18 | M1.3 | N12W39 | 3038 | |
| 21:12 | 21:18 | 63 | X1.3 | N11W47 | 3038 |
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.
← M5.5 1981-04-18X1.3 1981-04-18 →
About this page
A X1.0 flare that began 1981-04-18 10:44 UTC; No. 32 of 4,022 C-class-or-larger flares in 1981.