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X1.3 solar flare on 1981-04-18
ClassX1.3NOAA report
Peak21:181981-04-18 UTC
Duration63 min
Peak flux1.3e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 298 / 491 |
| Rank in year | 25 / 4022 |
| Other M/X flares that day | 5 |
| M/X flares that month | 87 |
| Solar cycle | Cycle 21 |
| Position on disk | N11W47 |
| Active region | AR 3038 (26 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 |
|---|---|---|---|---|---|---|
| 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 | |
| 10:44 | 10:54 | 40 | X1.0 | – | – |
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 1981-04-18X1.0 1981-04-20 →
About this page
A X1.3 flare that began 1981-04-18 21:12 UTC; No. 25 of 4,022 C-class-or-larger flares in 1981.