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X4.0 solar flare on 1981-02-26
ClassX4.0NOAA report
Peak19:531981-02-26 UTC
Duration41 min
Peak flux4.0e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 68 / 491 |
| Rank in year | 3 / 4022 |
| Other M/X flares that day | 3 |
| M/X flares that month | 44 |
| Solar cycle | Cycle 21 |
| Position on disk | S15E50 |
| Active region | AR 2958 (20 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 |
|---|---|---|---|---|---|---|
| 14:21 | 14:26 | 17 | X1.8 | S12E53 | 2958 | |
| 18:45 | 20:00 | 315 | M2.4 | S18E35 | 2954 | |
| 23:33 | 23:33 | 21 | M1.2 | S14E44 | 2958 |
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.
← X1.8 1981-02-26M8.9 1981-03-22 →
About this page
A X4.0 flare that began 1981-02-26 19:22 UTC; No. 3 of 4,022 C-class-or-larger flares in 1981.