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X2.4 solar flare on 1981-02-20
ClassX2.4NOAA report
Peak06:431981-02-20 UTC
Duration67 min
Peak flux2.4e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 152 / 491 |
| Rank in year | 11 / 4022 |
| Other M/X flares that day | 1 |
| M/X flares that month | 44 |
| Solar cycle | Cycle 21 |
| Position on disk | N19W49 |
| Active region | AR 2941 (11 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 |
|---|---|---|---|---|---|---|
| 05:49 | 05:50 | 45 | M1.1 | N12W38 | 2947 |
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.
← M8.3 1981-02-19M5.2 1981-02-24 →
About this page
A X2.4 flare that began 1981-02-20 06:40 UTC; No. 11 of 4,022 C-class-or-larger flares in 1981.